{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T04:05:28Z","timestamp":1790827528437,"version":"4.1.0"},"reference-count":14,"publisher":"BMJ","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Med Genet"],"published-print":{"date-parts":[[1985,4]]},"abstract":"<jats:p>Chromosome analysis using conventional staining, G banding, and, after BUdR incorporation, two R banding methods, one using Hoechst and one acridine orange, were performed on lymphocytes from a pair of female monozygotic twins. The culture conditions were designed to show the presence of the fragile X (q27-28) which had previously been found to be segregating in the family. One twin was of higher than normal intelligence and the other had been diagnosed as mentally retarded. The frequency of the occurrence of the early\/active fragile X compared to the overall total of informative fragile X was determined using both methods described above and was also compared with previous published data in the form of a graph showing percentage of early\/active fragile X against intelligence.<\/jats:p>","DOI":"10.1136\/jmg.22.2.85","type":"journal-article","created":{"date-parts":[[2008,11,10]],"date-time":"2008-11-10T15:09:16Z","timestamp":1226329756000},"page":"85-91","source":"Crossref","is-referenced-by-count":40,"title":["Frequency and replication status of the fragile X, fra(X)(q27-28), in a pair of monozygotic twins of markedly differing intelligence."],"prefix":"10.1136","volume":"22","author":[{"given":"E","family":"Tuckerman","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"T","family":"Webb","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S E","family":"Bundey","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[1985,4,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1111\/j.1469-1809.1984.tb00830.x","article-title":"The marker (X) syndrome: a cytogenetic and genetic analysis","volume":"48","author":"Sherman, S.L.; Morton, N.E.; Jacobs, P.A.; Turner, G.","year":"1984","unstructured":"Sherman SL, Morton NE, Jacobs PA, Turner G. 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Clinical and cytogenetic manifestation in heterozygotes and hemizygotes of five kindreds","volume":"60","author":"Schmidt, A.","year":"1982","unstructured":"Schmidt A. Fragile site Xq27 and mental retardation. Clinical and cytogenetic manifestation in heterozygotes and hemizygotes of five kindreds. Humn Genet 1982;60:322-7.","journal-title":"Humn Genet"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1002\/ajmg.1320140412","article-title":"Relationship between agc and intelligence and the frequency of expression of fragile(X) (q28)","volume":"14","year":"1983","unstructured":"Relationship between agc and intelligence and the frequency of expression of fragile(X) (q28). Am J Med Genet 1983;14:699-712.","journal-title":"Am J Med Genet"},{"key":"ref_6","first-page":"\"241","article-title":"Familial variation in the proportion of lymphocytes with the fragile site in males","volume":"17","author":"Jacobs, P.A.; Mayer, Glover T.W.; M.","year":"1984","unstructured":"Familial variation in the proportion of lymphocytes with the fragile site in males. Am J Med Genet 1984;17:241-53. Jacobs PA, Glover TW. Mayer M, et al. X-linked mental retardation: a study of seven families. Am J Med Genet 1980;7:471-90.","journal-title":"Am J Med Genet; X-linked mental retardation: a study of seven families"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"278","DOI":"10.1007\/BF00303019","article-title":"Replication pattern in XXY cells with fra(X)","volume":"60","author":"Froster-Iskenius, J.; Schwinger, E.; Weigert, M.; Fonatsch, C.","year":"1982","unstructured":"Froster-Iskenius J, Schwinger E, Weigert M, Fonatsch C. Replication pattern in XXY cells with fra(X). 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Am J Hum Genet 1969;21:231-44.","journal-title":"Am J Hum Genet"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1111\/j.1469-185X.1972.tb00969.x","article-title":"X-chromosome inactivation and developmental patterns in mammals","volume":"47","author":"Lyon, M.F.","year":"1972","unstructured":"Lyon MF. X-chromosome inactivation and developmental patterns in mammals. Biol Rev 1972;47:1-35.","journal-title":"Biol Rev"},{"key":"ref_14","first-page":"35","article-title":"Conference report. Replication studies in heterozygotes for fragile X","volume":"17","author":"Sutherland, G.","year":"1984","unstructured":"Sutherland G. Conference report. Replication studies in heterozygotes for fragile X. 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