{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,19]],"date-time":"2026-02-19T07:52:08Z","timestamp":1771487528621,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2012,3,2]],"date-time":"2012-03-02T00:00:00Z","timestamp":1330646400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>RT-qPCR is commonly employed in gene expression studies in ectopic pregnancy. Most use RN18S1, \u03b2-actin or GAPDH as internal controls without validation of their suitability as reference genes. A systematic study of the suitability of endogenous reference genes for gene expression studies in ectopic pregnancy is lacking. The aims of this study were therefore to evaluate the stability of 12 reference genes and suggest those that are stable for use as internal control genes in fallopian tubes and endometrium from ectopic pregnancy and healthy non-pregnant controls. Analysis of the results showed that the genes consistently ranked in the top six by geNorm and NormFinder algorithms, were UBC, GAPDH, CYC1 and EIF4A2 (fallopian tubes) and UBC and ATP5B (endometrium). mRNA expression of NAPE-PLD as a test gene of interest varied between the groups depending on which of the 12 reference genes was used as internal controls. This study demonstrates that arbitrary selection of reference genes for normalisation in RT-qPCR studies in ectopic pregnancy without validation, risk producing inaccurate data and should therefore be discouraged.<\/jats:p>","DOI":"10.3390\/ijms13032810","type":"journal-article","created":{"date-parts":[[2012,3,5]],"date-time":"2012-03-05T07:40:22Z","timestamp":1330933222000},"page":"2810-2826","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Variation in Stability of Endogenous Reference Genes in Fallopian Tubes and Endometrium from Healthy and Ectopic Pregnant Women"],"prefix":"10.3390","volume":"13","author":[{"given":"Alpha K.","family":"Gebeh","sequence":"first","affiliation":[{"name":"Endocannabinoid Research Group, Reproductive Science Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, LE2 7LX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Emma L.","family":"Marczylo","sequence":"additional","affiliation":[{"name":"Systems Toxicology, MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester, LE1 9HN, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akwasi A.","family":"Amoako","sequence":"additional","affiliation":[{"name":"Endocannabinoid Research Group, Reproductive Science Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, LE2 7LX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathon M.","family":"Willets","sequence":"additional","affiliation":[{"name":"Endocannabinoid Research Group, Reproductive Science Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, LE2 7LX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Justin C.","family":"Konje","sequence":"additional","affiliation":[{"name":"Endocannabinoid Research Group, Reproductive Science Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, LE2 7LX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2012,3,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1016\/S0140-6736(05)67103-6","article-title":"Ectopic pregnancy","volume":"366","author":"Farquhar","year":"2005","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1111\/j.1471-0528.2010.02847.x","article-title":"Saving Mothers\u2019 Lives: Reviewing maternal deaths to make motherhood safer: 2006\u20132008. The Eighth Report of the Confidential Enquiries into Maternal Deaths in the United Kingdom","volume":"118","author":"Cantwell","year":"2011","journal-title":"BJOG"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1097\/00003081-199903000-00004","article-title":"Incidence and risk factors for ectopic pregnancy","volume":"42","author":"Pisarska","year":"1999","journal-title":"Clin. Obstet. Gynecol"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1586\/eog.10.61","article-title":"Molecular mechanisms of tubal pregnancy","volume":"5","author":"Gebeh","year":"2010","journal-title":"Expert Rev. Obstet. Gynecol"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"856","DOI":"10.1016\/j.bbrc.2003.11.177","article-title":"Guideline to reference gene selection for quantitative real-time PCR","volume":"313","author":"Radonic","year":"2004","journal-title":"Biochem. Biophys. Res. Commun"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1038\/sj.gene.6364190","article-title":"Real-time RT-PCR normalisation; strategies and considerations","volume":"6","author":"Huggett","year":"2005","journal-title":"Genes Immun"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1677\/jme.0.0250169","article-title":"Absolute quantification of mRNA using real-time reverse transcription polymerase chain reaction assays","volume":"25","author":"Bustin","year":"2000","journal-title":"J. Mol. Endocrinol"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1677\/jme.0.0290023","article-title":"Quantification of mRNA using real-time reverse transcription PCR (RT-PCR): Trends and problems","volume":"29","author":"Bustin","year":"2002","journal-title":"J. Mol. Endocrinol"},{"key":"ref_9","first-page":"500","article-title":"Housekeeping genes as a reference in quantitative real-time RT-PCR","volume":"61","author":"Romanowski","year":"2007","journal-title":"Postepy Hig. Med. Dosw"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1016\/S0301-472X(02)00806-8","article-title":"Gene quantification using real-time quantitative PCR: An emerging technology hits the mainstream","volume":"30","author":"Ginzinger","year":"2002","journal-title":"Exp. Hematol"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"611","DOI":"10.1373\/clinchem.2008.112797","article-title":"The MIQE guidelines: Minimum information for publication of quantitative real-time PCR experiments","volume":"55","author":"Bustin","year":"2009","journal-title":"Clin. Chem"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"921","DOI":"10.1016\/j.cca.2010.03.012","article-title":"Endocannabinoids and pregnancy","volume":"411","author":"Taylor","year":"2010","journal-title":"Clin. Chim. Acta"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2910","DOI":"10.3390\/ph3092910","article-title":"From fertilisation to implantation in mammalian pregnancy-modulation of early human reproduction by the endocannabinoid system","volume":"3","author":"Bambang","year":"2010","journal-title":"Pharmaceuticals"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"288","DOI":"10.1016\/j.jbiotec.2010.09.949","article-title":"Selection of reference genes for gene expression studies in porcine skeletal muscle using SYBR green qPCR","volume":"150","author":"Feng","year":"2010","journal-title":"J. Biotechnol"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Hoogewijs, D., Houthoofd, K., Matthijssens, F., Vandesompele, J., and Vanfleteren, J.R. (2008). Selection and validation of a set of reliable reference genes for quantitative sod gene expression analysis in Caenorhabditis elegans. BMC Mol. Biol, 9.","DOI":"10.1186\/1471-2199-9-9"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"5461","DOI":"10.3390\/ijms12095461","article-title":"Selection of candidate housekeeping genes for normalization in human postmortem brain samples","volume":"12","author":"Penna","year":"2011","journal-title":"Int. J. Mol. Sci"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"557","DOI":"10.1007\/s00418-010-0695-9","article-title":"Histomorphometric evaluation of cannabinoid receptor and anandamide modulating enzyme expression in the human endometrium through the menstrual cycle","volume":"133","author":"Taylor","year":"2010","journal-title":"Histochem. Cell Biol"},{"key":"ref_18","unstructured":"(2007). geNorm, version 3.5; Center for Medical Genetics, Ghent University."},{"key":"ref_19","unstructured":"(2005). NormFinder, version 0.953, Aarhus University Hospital."},{"key":"ref_20","unstructured":"(2011). GenEx software, version 5.3.6.170, MultiD Analyses AB."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"RESEARCH0034.1","DOI":"10.1186\/gb-2002-3-7-research0034","article-title":"Accurate normalization of real-time quantitative RT-PCR data by geometric averaging of multiple internal control genes","volume":"3","author":"Vandesompele","year":"2002","journal-title":"Genome Biol"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"5245","DOI":"10.1158\/0008-5472.CAN-04-0496","article-title":"Normalization of real-time quantitative reverse transcription-PCR data: A model-based variance estimation approach to identify genes suited for normalization, applied to bladder and colon cancer data sets","volume":"64","author":"Andersen","year":"2004","journal-title":"Cancer Res"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1186\/1471-2199-11-39","article-title":"Validation of endogenous reference genes for qRT-PCR analysis of human visceral adipose samples","volume":"11","author":"Mehta","year":"2010","journal-title":"BMC Mol. Biol"},{"key":"ref_24","unstructured":"(2009). GraphPad Prism, version 5.00, GraphPad Software."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/13\/3\/2810\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:49:11Z","timestamp":1760219351000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/13\/3\/2810"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,3,2]]},"references-count":24,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2012,3]]}},"alternative-id":["ijms13032810"],"URL":"https:\/\/doi.org\/10.3390\/ijms13032810","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,3,2]]}}}