A rare mutation in the primer binding region of the amelogenin gene can interfere with gender identification.
PCR amplification of part of the X-Y homologous amelogenin gene with a single primer pair has been used as a sex identification test because it generates different length products from the X and Y chromosomes. Using a commercially available kit that contains amelogenin primers, we report a single phenotypically normal Caucasian male out of 327 males tested to date that failed to show an X chromosome-specific PCR product. Using alternative amelogenin primers external to but encompassing the initial amplicon, an X chromosome-specific product was seen. Sequence analysis of this X-specific PCR product revealed a C to G mutation at the most 3' base of the initial reverse amelogenin PCR primer. An alternative reverse PCR primer with this most 3' base deleted showed X- and Y-specific products from the case study male. Rare mutations that result in a failure to amplify sex chromosome-specific products can result in incorrect gender identification.
Shadrach
Bonnie
B
Department of Clinical Pathology/L30, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
Commane
Mairead
M
Hren
Carol
C
Warshawsky
Ilka
I
D000483:Alleles; D053523:Amelogenin; D041321:Chromosomes, Human, X; D017931:DNA Primers / Q000737:chemistry; D003746:Dental Enamel Proteins / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D009154:Mutation; D016133:Polymerase Chain Reaction / Q000379:methods*; D011485:Protein Binding; D017422:Sequence Analysis, DNA / Q000379:methods; D012732:Sex Determination Analysis / Q000379:methods*
D053523:Amelogenin; D017931:DNA Primers; D003746:Dental Enamel Proteins