Polymorphisms within a polymorphism: SNPs in and around a polymorphic Alu insertion in intron 44 of the human dystrophin gene.
A polymorphic Yb-type Alu insertion on Xp21.3 shows a genotypic gradient across worldwide populations. We used single strand conformational polymorphism (SSCP), denaturing high-pressure liquid chromatography (DHPLC), and sequencing to characterize the level of polymorphism within this region. Two novel polymorphic sites were found within the Alu insertion itself, and a further seven novel polymorphic sites in the 2-kb flanking region. Our results showed that while DHPLC was more sensitive than SSCP, the limitations of DHPLC included the lack of ability to distinguish between multiple alleles or safely identify mutations on a polymorphic background. We believe that this is the first report of polymorphic single nucleotide polymorphisms (SNPs) within a polymorphic Alu distribution and that together they promise to provide a useful marker for human population and evolutionary genetics.
Lovell
Alan D
AD
Centre de Recherche, Hôpital Sainte-Justine, 3175 Côte-Ste-Catherine, Montréal, QC, Canada, H3T 1C5.
Yotova
Vania
V
Xiao
Fengxia
F
Batzer
Mark A
MA
Labuda
Damian
D
D017954:Africa South of the Sahara; D020087:Alu Elements / Q000235:genetics*; D000569:Americas; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000737:chemistry / Q000235:genetics; D016189:Dystrophin / Q000235:genetics*; D005060:Europe; D005202:Asia, Eastern; D005260:Female; D005787:Gene Frequency; D005843:Geography; D006801:Humans; D007438:Introns / Q000235:genetics*; D008297:Male; D008877:Middle East; D016254:Mutagenesis, Insertional / Q000235:genetics; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D018807:Polymorphism, Single-Stranded Conformational; D017422:Sequence Analysis, DNA
D016189:Dystrophin; D004247:DNA