{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T22:03:13Z","timestamp":1791324193505,"version":"4.3.1"},"reference-count":62,"publisher":"American Association for the Advancement of Science (AAAS)","issue":"5529","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Science"],"published-print":{"date-parts":[[2001,7,20]]},"abstract":"<jats:p>\n                    The frequencies of low-activity alleles of glucose-6-phosphate dehydrogenase in humans are highly correlated with the prevalence of malaria. These \u201cdeficiency\u201d alleles are thought to provide reduced risk from infection by the\n                    <jats:italic>Plasmodium<\/jats:italic>\n                    parasite and are maintained at high frequency despite the hemopathologies that they cause. Haplotype analysis of \u201cA\u2212\u201d and \u201dMed\u201c mutations at this locus indicates that they have evolved independently and have increased in frequency at a rate that is too rapid to be explained by random genetic drift. Statistical modeling indicates that the A\u2212 allele arose within the past 3840 to 11,760 years and the Med allele arose within the past 1600 to 6640 years. These results support the hypothesis that malaria has had a major impact on humans only since the introduction of agriculture within the past 10,000 years and provide a striking example of the signature of selection on the human genome.\n                  <\/jats:p>","DOI":"10.1126\/science.1061573","type":"journal-article","created":{"date-parts":[[2002,7,27]],"date-time":"2002-07-27T05:39:52Z","timestamp":1027748392000},"page":"455-462","source":"Crossref","is-referenced-by-count":477,"title":["Haplotype Diversity and Linkage Disequilibrium at Human\n                    <i>G6PD<\/i>\n                    : Recent Origin of Alleles That Confer Malarial Resistance"],"prefix":"10.1126","volume":"293","author":[{"given":"Sarah A.","family":"Tishkoff","sequence":"first","affiliation":[{"name":"Department of Biology, Biology\/Psychology Building, University of Maryland, College Park, MD 20742, USA."},{"name":"Institute of Evolutionary Genetics, Department of Biology, Pennsylvania State University, University Park, PA 16802, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Varkonyi","sequence":"additional","affiliation":[{"name":"Institute of Evolutionary Genetics, Department of Biology, Pennsylvania State University, University Park, PA 16802, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nelie","family":"Cahinhinan","sequence":"additional","affiliation":[{"name":"Institute of Evolutionary Genetics, Department of Biology, Pennsylvania State University, University Park, PA 16802, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salem","family":"Abbes","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and Pasteur Institute, Tunis, Tunisia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George","family":"Argyropoulos","sequence":"additional","affiliation":[{"name":"Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA 70808, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni","family":"Destro-Bisol","sequence":"additional","affiliation":[{"name":"Department of Human and Animal Biology, University \u201cLa Sapienza,\u201d Rome, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anthi","family":"Drousiotou","sequence":"additional","affiliation":[{"name":"Department of Biochemical Genetics, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruce","family":"Dangerfield","sequence":"additional","affiliation":[{"name":"Department of Human Genetics, South African Institute of Medical Research, University of the Witwatersrand, Johannesburg, South Africa."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gerard","family":"Lefranc","sequence":"additional","affiliation":[{"name":"University of Sciences and CNRS, Montpellier, France."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacques","family":"Loiselet","sequence":"additional","affiliation":[{"name":"University St. Joseph, Beirut, Lebanon."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Piro","sequence":"additional","affiliation":[{"name":"Istituto di Medicina Sperimentale e Biotecnologie\u2013CNR, Mangone (Cosenza), Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Stoneking","sequence":"additional","affiliation":[{"name":"Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Tagarelli","sequence":"additional","affiliation":[{"name":"Istituto di Medicina Sperimentale e Biotecnologie\u2013CNR, Mangone (Cosenza), Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Tagarelli","sequence":"additional","affiliation":[{"name":"Istituto di Medicina Sperimentale e Biotecnologie\u2013CNR, Mangone (Cosenza), Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elias H.","family":"Touma","sequence":"additional","affiliation":[{"name":"University St. Joseph, Beirut, Lebanon."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Scott M.","family":"Williams","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Meharry Medical College, Nashville, TN 37208, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew G.","family":"Clark","sequence":"additional","affiliation":[{"name":"Institute of Evolutionary Genetics, Department of Biology, Pennsylvania State University, University Park, PA 16802, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"221","reference":[{"key":"e_1_3_1_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/0168-9525(92)90080-N"},{"key":"e_1_3_1_3_2","doi-asserted-by":"publisher","DOI":"10.1182\/blood.V84.11.3613.bloodjournal84113613"},{"key":"e_1_3_1_4_2","doi-asserted-by":"publisher","DOI":"10.1007\/s001090050253"},{"key":"e_1_3_1_5_2","unstructured":"L. Luzatto A. Mehta T. Vulliamy in The Metabolic and Molecular Bases of Inherited Disease C. R. Scriver A. L. Beaudet W. S. Sly D. Valle Eds. (McGraw-Hill New York ed. 8 2001) pp. 4517\u20134553."},{"key":"e_1_3_1_6_2","doi-asserted-by":"publisher","DOI":"10.1038\/376246a0"},{"key":"e_1_3_1_7_2","doi-asserted-by":"publisher","DOI":"10.1182\/blood.V74.7.2550.bloodjournal7472550"},{"key":"e_1_3_1_8_2","unstructured":"DNA was isolated by standard phenol-chloroform extraction and\/or a Gentra PureGene kit. All samples are from unrelated individuals and were obtained with informed consent and with the approval of the human subjects review panels of participating institutions. The Papua New Guinean samples come from both highland and coastal locations (48). The Bantu-speaking populations are from ethnically mixed South African Bantu speakers. The Mende and Temne ethnic groups originate from Sierra Leone (49) the Ga originate from Ghana (50) and the Bakaka from Cameroon (51). We also included samples from assorted ethnic groups originating from Sierra Leone (Creole Fula Limba Loko Mandingo) Ghana (Akan Ashante Ewe) and Cameroon (Mandara Podoko Uldeme Bassa) for which the samples sizes were very small and therefore were grouped together and analyzed as \u201cMixed.\u201d The Cypriot samples are from individuals whose parents are both Greek Orthodox and originate from both coastal and mountainous districts of the island. The Italian samples all originate from the Ionian coast of the Calabria region of southern Italy (11 21). The Tunisian samples are from unrelated patients from different parts of Tunisia and the Lebanese samples originate from unrelated samples collected in Beirut."},{"key":"e_1_3_1_9_2","unstructured":"The G6PD B A and A\u2212 alleles in Africa were distinguished by PCR amplification of exons 3 and 4 followed by digestion with Nla III restriction enzyme and by amplification of exon 5 followed by digestion with Fok I. Individuals who lack both restriction sites were classified as B those who lacked the Nla III site but contained the Fok I site were classified as A and those who had both Nla III and Fok I restriction sites were classified as A\u2212. Primers used to amplify exons 3 and 4 were G6PD3\/4F (5\u2032-AACCACACACCTGTTCCCTC-3\u2032) and G6PD 3\/4R (5\u2032-GCTGGTAGAGAGGGCAGAAC-3\u2032). Amplification with these primers produces a 320-bp product and digestion with Nla III produces 207- and 113-bp fragments in individuals with the A\u2212 mutation and a 320-bp fragment in individuals who lack the mutation. Primers used to amplify exon 5 were G6PD5F (5\u2032-CAAAGAGAGGGGCTGACATC-3\u2032) and G6PD5R (5\u2032-GCTCATAGAGTGGTGGGAGC-3\u2032). Amplification with these primers produced a 342-bp product. Digestion with Fok I produces 173- and 169-bp fragments if the individual has the A mutation. The Med mutation can be detected by amplification of exon 6 followed by digestion with Mbo II. Primers used to amplify exon 6 were G6PD6F (5\u2032-TGCAGCTGTGATCCTCACTC-3\u2032) and G6PD6R (5\u2032-AGGTGGAGGAACTGACCTTG-3\u2032). Amplification produces a 388-bp product. Digestion with Mbo II produces 253- 99- and 36-bp fragments in individuals with the Med mutation and produces 352- and 36-bp fragments in individuals who lack the mutation. Amplifications were performed with 50 to 100 ng of genomic DNA in a 25-\u03bcl (total volume) reaction mixture. The reaction mixture contained 10 pmol of each forward and reverse primer 200 \u03bcM of each deoxynucleotide triphosphate (dNTP) 50 mM KCl 10 mM tris-HCl 1.5 mM MgCl 2 and 0.625 U of Taq polymerase. Exons 3\/4 and exon 5 samples were denatured for 1 min at 94\u00b0C followed by 30 cycles of 94\u00b0C for 1 min 58\u00b0C for 1 min and 72\u00b0C for 1 min followed by a 10-min extension at 72\u00b0C. Exon 6 samples were denatured for 1 min at 94\u00b0C followed by 30 cycles of 94\u00b0C for 1 min 59\u00b0C for 1 min and 72\u00b0C for 1 min followed by a 10-min extension at 72\u00b0C. PCR products were digested for 2 hours overnight with the appropriate restriction enzymes buffers and incubation temperatures. Amplification products were run on a 1% agarose gel stained with ethidium bromide and visualized with an ultraviolet transilluminator and photoimager. The Pst I and Bsp HI RFLPs were detected with the primers and protocols as described in (13) and (12) respectively. The Sca I and Bsp I restriction sites were created by mismatch-containing primers to detect the underlying mutations as described (12)."},{"key":"e_1_3_1_10_2","unstructured":"The Tunisian and non-African samples were selected on the basis of G6PD protein electrophoretic properties and\/or enzyme activity levels. For the Tunisian populations electrophoretic mobility and enzyme activity of G6PD was performed with the standard World Health Organization protocol as described (52). Enzyme activity levels for the Lebanese and Cypriot samples were measured by a semiquantitative fluorescence test (53). Enzyme activity level in the Italian population was measured by differential pH-metry as described (54). For the Italian sample only those individuals with enzyme activity levels less than 5% of normal were included in the study."},{"key":"e_1_3_1_11_2","first-page":"267","volume":"16","author":"Plato C. C.","year":"1964","unstructured":"Plato C. C., Rucknagel D. L., Gershowitz H., Am. J. Hum. Genet. 16, 267 (1964).","journal-title":"Am. J. Hum. Genet."},{"key":"e_1_3_1_12_2","first-page":"141","volume":"5","author":"Tagarelli A.","year":"1991","unstructured":"Tagarelli A., et al., Gene Geogr. 5, 141 (1991).","journal-title":"Gene Geogr."},{"key":"e_1_3_1_13_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.88.19.8568"},{"key":"e_1_3_1_14_2","first-page":"1008","volume":"47","author":"Beutler E.","year":"1990","unstructured":"Beutler E., Kuhl W., Am. J. Hum. Genet. 47, 1008 (1990).","journal-title":"Am. J. Hum. Genet."},{"key":"e_1_3_1_15_2","unstructured":"GenBank accession number ."},{"key":"e_1_3_1_16_2","unstructured":"The G6PD A A\u2212 and Med mutations were not detected in a sample of 11 great apes. In 16 chromosomes screened from chimps ( n = 13) and gorillas ( n = 3) we observed microsatellite allele sizes that overlap the range observed in humans with the exception of six 196-bp and three 152-bp AC alleles observed in chimps and gorillas respectively and 180- to 192-bp CTT alleles observed in both chimps and gorillas (55)."},{"key":"e_1_3_1_17_2","unstructured":"The (AC) n repeat was amplified with primers ACF (5\u2032-TCACTTGGGCCATGATCAC-3\u2032) and ACR (5\u2032-TTAATTTGTATCATGGGGTCCTAG-3\u2032) that produce fragments from 164- to 188-bp long. The (AT) n repeat was amplified with primers ATF (5\u2032-CATGGTTTCTGTGGAGTCTAGC-3\u2032) and ATR (5\u2032-GGTGGGAGGATTGCTTGAAG-3\u2032) that produce fragments from 125- to 179-bp long. The (CTT) n repeat was amplified with primers CTTF (5\u2032-GTTCAAGCGATTCTAGTGCCC3\u2032) and CTTR (5\u2032-CGGGTAGATTGCTTGAGCC-3\u2032) that amplify fragments from 195- to 216-bp long. Amplification was performed with 50 ng of genomic DNA in a 25-\u03bcl (total volume) reaction mixture. The reaction mixture contained 5 pmol each of fluorescently labeled forward and reverse primer 200 \u03bcM of each dNTP 50 mM KCl 10 mM tris-HCl 1.5 mM MgCl 2 and 0.625 U of Taq polymerase. Samples were denatured for 1 min at 94\u00b0C followed by 25 cycles of 94\u00b0C for 1 min 56\u00b0C for 1 min and 72\u00b0C for 1 min followed by a 10-min extension at 72\u00b0C. Amplification products were run on a 6% polyacrylamide gel on an ABI 373 DNA sequencer and fragment sizes were determined with Genescan software. Amplification of the CTT repeat which is located within an Alu -rich region produces some nonspecific fragments (predominantly a 154-bp band) that do not vary among individuals. Only bands between 195 and 216 bp in size are polymorphic."},{"key":"e_1_3_1_18_2","unstructured":"Supplementary Web material is available on Science Online at www.sciencemag.org\/cgi\/content\/full\/1061573\/DC1."},{"key":"e_1_3_1_19_2","unstructured":"Although data from males provide unambiguous linkage phase of the restriction sites and microsatellite alleles linkage phase in females can be ambiguous. The usual expectation-maximization (EM) algorithms that have been used to infer haplotype phase (56) are inadequate for such data because these algorithms exhaustively enumerate potential haplotypes. With three microsatellites having 10 26 and 8 alleles segregating in the population there are 2080 (10 \u00d7 26 \u00d7 8) potential haplotypes and the likelihood surface is nearly flat. Instead haplotypes were inferred in a two-tiered process first by applying the algorithm of Clark (57) followed by EM to obtain maximum likelihood estimates of frequencies and likelihoods of alternative phases for ambiguous individuals. The algorithm of Clark (57) identifies haplotypes that are unambiguous either by virtue of homozygosity (or hemizygosity as in the case of X-linked genes in males) or if the two haplotypes in a female differ by only a single site. Because the data consisted of \u223c80% males (Table 1) we have an extensive starting set of known haplotypes. Remaining individuals with ambiguous linkage phase are then tested to see if any of the confirmed haplotypes might be borne by those individuals. If so then a possible phase consists of that haplotype and the complement that gives the observed genotype. When the likely phasings are compiled for all individuals the EM is run to maximize the likelihood for a set of phasings."},{"key":"e_1_3_1_20_2","unstructured":"The allele frequencies of B A and A\u2212 variants were estimated by gene counting. Heterozygosities for individual sites and for the haplotypes were estimated as n (1 \u2212 \u03a3 p i 2 )\/( n \u2212 1) where p i represents the frequency of the i th allele or haplotype for any given system and n is the sample size."},{"key":"e_1_3_1_21_2","unstructured":"Owing to the large allele number of the microsatellites near G6PD classical tests of LD among microsatellites are inappropriate. However LD between the major G6PD alleles (B A A\u2212 Med) and each microsatellite locus could be tested with Fisher's exact test. Contingency tables were constructed from the haplotype counts in which columns were the G6PD functional allele and rows were the microsatellite alleles. Fisher's exact tests assessed whether the observed sample deviates from that expected under independent sampling of RFLPs and microsatellites."},{"key":"e_1_3_1_22_2","doi-asserted-by":"publisher","DOI":"10.1006\/geno.1993.1276"},{"key":"e_1_3_1_23_2","unstructured":"Coalescent simulations were run for each combination of A\u2212 versus Med allelic lineages and microsatellite locus (total of six runs). The sample from sub-Saharan Africa was drawn without ascertainment bias so the observation of 42 A\u2212 alleles in a sample of 315 chromosomes represents the population frequency used in the simulations. The other populations were ascertained nonrandomly so we used an estimate of 0.05 as the frequency of the Med allele in those populations (10 11) and we drew a sample from the observed Med haplotypes to reconstruct a population sample. In each simulation run 10 000 random coalescence trees were generated that satisfy the rejection criteria [that the derived clade have a frequency equal to the observed A\u2212 (or Med) clade and that the variance in the microsatellite allele size on the remaining clades be within \u00b120% of the observed variance]. The mutation rate of the microsatellite was sampled from a prior distribution determined from extrinsic data (the variance in the microsatellite allele size). From each coalescence tree that was accepted we calculated four sample statistics: (i) the number of distinct haplotypes; (ii) the variance in the microsatellite allele size; (iii) the linkage disequilibrium parameter \u03b4 for the microsatellite allele with the highest LD {where \u03b4 = 1 \u2212 frequency[modal microsatellite allele not on A\u2212 (or Med)clade]\/frequency[modal microsatellite allele on the A\u2212 (or Med) clade]}; and (iv) the F statistic from an ANOVA testing equal microsatellite size between the A\u2212 (or Med) clade and the rest of the genealogy. This process generated the null distributions of the four sample statistics conditioned on having a clade with the observed deficiency allele frequency. If a sample statistic obtained from the observed data falls far into the tails of the respective null distribution we conclude that a neutral model does not fit the data satisfactorily and that another factor(s) contributes to the variation."},{"key":"e_1_3_1_24_2","unstructured":"Because all the tests ended up being one-tailed (A\u2212 and Med chromosomes are depauperate in microsatellite variation) performing the tests assuming zero recombination is conservative. Furthermore incorporation of population growth would result in a more starlike phylogeny and would also inflate the variance of the A\u2212 and Med subclades relative to the rest of the tree. Thus simulations without population growth provide a conservative test. Finally human populations have shown some level of subdivision whereas the A\u2212 and Med alleles appear to have spread across fairly broad geographic regions. Incorporation of geographic structure would increase the number of haplotypes and inflate the variance of allele size and would make the observed patterns of high frequency high LD low microsatellite variability and broad geographic distribution even less likely under neutrality."},{"key":"e_1_3_1_25_2","doi-asserted-by":"publisher","DOI":"10.1093\/genetics\/145.2.519"},{"key":"e_1_3_1_26_2","doi-asserted-by":"publisher","DOI":"10.1093\/genetics\/155.2.909"},{"key":"e_1_3_1_27_2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.genom.1.1.225"},{"key":"e_1_3_1_28_2","unstructured":"The rejection method was applied to accept only those simulation runs that bore sufficient resemblance to the observed data. For each of the AC AT and CTT microsatellites we estimated the variance in the A\u2212 (or Med) clades the variance in the non-A\u2212 (or non-Med) clades and the LD between the A\u2212 (or Med) allele and the most common microsatellite allele. Each simulation produced values of these statistics. If the difference between any of the simulated statistics and the observed values exceeded 20% of the observed value that simulation was rejected. This criterion reflects a compromise between overly small values rejecting too large a proportion of the simulations and too large a value which leads to spuriously inflated variance in the posterior distributions. Altogether 37 052 runs that satisfied the rejection criteria were collected for the A\u2212 simulations and 38 362 for the Med simulations. For the simulation runs not rejected many attributes were collected including the time required for the A\u2212 or Med clade to expand to its current frequency."},{"key":"e_1_3_1_29_2","unstructured":"For each iteration of the simulation values of \u03bc s and r were drawn from a uniform prior distribution with the following ranges: \u03bc (10 \u22123 to 10 \u22124 ) s (0 to 0.1) and r (0 to 10 \u22124 ). Given an initial population size of 10 000 and a growth rate of \u03b3 = 0.001 per generation the allele frequencies were iterated until the population attained a frequency of the A\u2212 clade equal to that observed in the African sample ( q crit = 0.11) or of the Med clade equal to that estimated for the Mediterranean populations ( q crit = 0.05). The dominance and overdominance selection models produced estimates of mutation rate recombination rate and allele age that were all within 10% of each other (because A\u2212\/A\u2212 females are relatively rare in the early stages of allele expansion). The estimates of mean age of deficiency clades varied only by about 5% across the 10-fold range of growth rates suggesting that the estimates were robust across a range of population growth rates as long as the population is growing fast enough to make the branching process supercritical (i.e. growing sufficiently rapidly that the deficiency lineage is not lost). Similarly mean allele age estimates were relatively insensitive to the initial population size (varying only 2% across a range of sizes from 10 000 to 100 000). Although we expect the mutation rate and recombination rate to be the same in Africa as in the Mediterranean these two parameters were estimated independently in the two samples. The consistency of estimates of mutation rate and recombination in these two samples serves to test one aspect of validity of the model namely whether it converges on biologically consistent estimates."},{"key":"e_1_3_1_30_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.93.25.14771"},{"key":"e_1_3_1_31_2","unstructured":"To examine the effect of our assumption that the Med allele frequency was 0.05 we repeated the simulations described above assuming a G6PD Med allele frequency ( q ) equal to 0.02 or 0.10 representing the range of observed allele frequencies in the populations studied. With q = 0.10 we estimated a mean allele age of 4244 years with a 95% credibility interval of 2280 to 8400 years and with q = 0.02 we estimated a mean allele age of 2183 years with a 95% credibility interval of 840 to 4720 years."},{"key":"e_1_3_1_32_2","unstructured":"B. C. Verrelli S. A. Tishkoff unpublished data."},{"key":"e_1_3_1_33_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.271.5254.1380"},{"key":"e_1_3_1_34_2","doi-asserted-by":"publisher","DOI":"10.1086\/301861"},{"key":"e_1_3_1_35_2","doi-asserted-by":"publisher","DOI":"10.1086\/303068"},{"key":"e_1_3_1_36_2","doi-asserted-by":"publisher","DOI":"10.1086\/302952"},{"key":"e_1_3_1_37_2","doi-asserted-by":"publisher","DOI":"10.1525\/aa.1958.60.3.02a00110"},{"key":"e_1_3_1_38_2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.ge.05.120171.000341"},{"key":"e_1_3_1_39_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.157.3793.1134"},{"key":"e_1_3_1_40_2","unstructured":"I. W. Sherman in Malaria: Parasite Biology Pathogenesis and Protection I. W. Sherman Ed. (American Society for Microbiology Washington DC 1998) pp. 3\u201310."},{"key":"e_1_3_1_41_2","unstructured":"A. Brooks personal communication."},{"key":"e_1_3_1_42_2","unstructured":"A. S. Brooks P. T. Robershaw in The World at 18 000 BP vol. 2 Low Latitudes O. Soffer C. Gamble Eds. (Unwin Hyman London 1990) pp. 121\u2013169."},{"key":"e_1_3_1_43_2","first-page":"277","volume":"41","author":"Coluzzi M.","year":"1999","unstructured":"Coluzzi M., Parassitologia 41, 277 (1999).","journal-title":"Parassitologia"},{"key":"e_1_3_1_44_2","doi-asserted-by":"crossref","unstructured":"J. E. Yellen. Afr. Archaeol. Rev. 15 173 (1998).","DOI":"10.1023\/A:1021659928822"},{"key":"e_1_3_1_45_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.97.13.6994"},{"key":"e_1_3_1_46_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0166-6851(99)00162-0"},{"key":"e_1_3_1_47_2","unstructured":"L. L. Cavalli-Sforza A. Piazza P. Menozzi History and Geography of Human Genes (Princeton Univ. Press Princeton NJ 1994)."},{"key":"e_1_3_1_48_2","unstructured":"F. Durando Ancient Greece; The Dawn of the Western World (Syewart Tabori and Chang New York 1997)."},{"key":"e_1_3_1_49_2","doi-asserted-by":"publisher","DOI":"10.1093\/genetics\/124.3.717"},{"key":"e_1_3_1_50_2","doi-asserted-by":"publisher","DOI":"10.1172\/JCI4115"},{"key":"e_1_3_1_51_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.HYP.36.1.2"},{"key":"e_1_3_1_52_2","doi-asserted-by":"publisher","DOI":"10.1002\/(SICI)1096-8644(199910)110:2<143::AID-AJPA3>3.0.CO;2-J"},{"key":"e_1_3_1_53_2","doi-asserted-by":"publisher","DOI":"10.1182\/blood.V49.3.467.467"},{"key":"e_1_3_1_54_2","unstructured":"E. Touma R. Kruithof G. Reclos in 7th International Congress of Inborn Errors and Metabolism Vienna Austria 21 to 25 May 1997 p. 26."},{"key":"e_1_3_1_55_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0014-5793(99)01776-7"},{"key":"e_1_3_1_56_2","unstructured":"S. A. Tishkoff et al. data not shown."},{"key":"e_1_3_1_57_2","doi-asserted-by":"publisher","DOI":"10.1093\/oxfordjournals.jhered.a111613"},{"key":"e_1_3_1_58_2","first-page":"111","volume":"7","author":"Clark A. G.","year":"1990","unstructured":"Clark A. G., Mol. Biol. Evol. 7, 111 (1990).","journal-title":"Mol. Biol. Evol."},{"key":"e_1_3_1_59_2","doi-asserted-by":"publisher","DOI":"10.1016\/0888-7543(87)90048-6"},{"key":"e_1_3_1_60_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.85.11.3951"},{"key":"e_1_3_1_61_2","unstructured":"To examine the possibility of sequence heterogeneity we sequenced (AC) n and (AT) n alleles in a set of geographically diverse individuals. The (AT) n repeat consists of perfect uninterrupted repeats in one European three Africans one Papua New Guinean and one chimpanzee sequence (with alleles ranging from 135 to 139 bp). At the AC repeat the 178-bp allele was sequenced in two Europeans and three Papua New Guineans and was found to be identical to the 178-bp allele published in GenBank. However two 166-bp alleles sequenced in two African individuals (a South African Bantu-speaker and a Mende individual from Sierra Leone) had the sequence (TA) 5 (AA) 1 (TA) 9 (CA) 10 which is 12 bp smaller than the 178-bp allele. This shorter allele was most likely the product of a single event because geographically diverse Africans have identical sequences suggesting that these A\u2212 alleles are identical by descent. Further sequencing analysis will be required to obtain a detailed understanding of the evolutionary history of the three microsatellite alleles. Sequencing conditions were as follows: for PCR products from individuals homozygous for microsatellite alleles alleles from (AC) n were amplified with primers ACSEQF (5\u2032-GAGACTGAGGTGGGAGGTTC-3\u2032) and ACSEQR (5\u2032-AAGGAAAAGTTCCTGGGTGG-3\u2032) which produce a 235-bp product. Alleles from (AT) n were amplified with newly designed primers ATSEQF (5\u2032-TGCATTTTATCACCCCCTTC-3\u2032) and ATSEQR (5\u2032-CAGCTAAGGTGGGCATAGTG-3\u2032) which produce a 248-bp product. Amplification was performed with 50 to 100 ng of genomic DNA in a 25-\u03bcl (total volume) reaction mixture. The reaction mixture contained 10 pmol of each forward and reverse primer 200 \u03bcM of each dNTP 50 mM KCl 10 mM tris-HCl 1.5 mM MgCl 2 and 0.625 U of Taq polymerase. Samples were denatured for 1 min at 94\u00b0C followed by 25 cycles of 94\u00b0C for 1 min 60\u00b0C for 1 min and 72\u00b0C for 1 min followed by a 10-min extension at 72\u00b0C. The amplified products were purified with a Qiagen PCR purification kit and were cycle sequenced with a Beckman CEQ DTCS sequencing kit. Products were run and analyzed on a Beckman CEQ2000 automated DNA sequencer."},{"key":"e_1_3_1_62_2","unstructured":"M. Saunders M. Hammer M. Nachman in preparation."},{"key":"e_1_3_1_63_2","unstructured":"Funded by a Burroughs Wellcome Fund Career Award NSF Sloan fellowship and NSF grants BCS-9905396 (S.A.T.) and DEB 9806655 (A.G.C.). S.M.W. was supported by grants K14-HL03321 (National Heart Lung and Blood Institute) G12-RR03032 (National Center for Research Resources) and T37-TW00043 (Fogarty Center NIH). E.H.T. and J.L. were supported by a grant from CNRS-Lebanon. We thank C. Gallo for technical assistance A. Deinard for providing chimpanzee and gorilla samples S. Gevao for assistance with collecting samples from Sierra Leone and M. Angastiniotis (Cyprus Thalassaemia Centre) for assistance with collecting samples in Cyprus. We also thank A. Brooks J. Friedlaender H. Harpending P. Hedrick N. Risch and B. Verrelli for critical review of the manuscript and for helpful discussion. S.A.T. thanks B. Dangerfield A. Krause and T. Jenkins for stimulating her interest in the G6PD locus and thanks the South African Institute of Medical Research and Trefor Jenkins' laboratory for hosting her as a visiting research scientist in 1997 during which time this work was initiated."}],"container-title":["Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.science.org\/doi\/pdf\/10.1126\/science.1061573","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,1,9]],"date-time":"2024-01-09T16:24:51Z","timestamp":1704817491000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.science.org\/doi\/10.1126\/science.1061573"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2001,7,20]]},"references-count":62,"journal-issue":{"issue":"5529","published-print":{"date-parts":[[2001,7,20]]}},"alternative-id":["10.1126\/science.1061573"],"URL":"https:\/\/doi.org\/10.1126\/science.1061573","relation":{},"ISSN":["0036-8075","1095-9203"],"issn-type":[{"value":"0036-8075","type":"print"},{"value":"1095-9203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2001,7,20]]}}}