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結果 (英文) 1:

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結果 (英文) 2:

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結果 (英文) 3:

The deletions of Y-STR loci can be explained by a mutation in the primer-binding site [13], large deletion surrounding the repeat regions leading to an absence of primer binding region [6], deletion of the entire area comprising deleted locus [14], or loss of a partial arm of Y chromosome [15]. In our study, samples showed null alleles at DYS389I, DYS389II, DYS437, and DYS448 were simultaneously typed with kits available from different manufacturers. It is unlikely that de- letions at these loci are due to the mutations in the primer- binding sites. Considering the physical positions in the Y chromosome (Table S2) and their independent deletions not involving neighboring loci, the occurrences of null alleles at DYS389I, DYS389II, DYS437, and DYS448 can be better explained by the deletion of an entire repeat region or the surrounding region of STR [6]. However, the null alleles ob- served at DYS446, DYS447, and DYS557 may result from the primer binding site variants, deletions of the target region, or the loss of locus.A total of 58 duplicated events were found in the unrelated individuals, and 56 out of them showed the duplicated alleles that differed by only a single repeat unit (Table 1). Furthermore, 50 of the 56 duplications at the bi-local markers (DYF387S1a/b, DYS385a/b, DYS459a/b, and DYS527a/b) only carried three alleles. It seems to be consistent with the stepwise mutation model (SMM) that has been applied to STR mutation. The additional allele at the duplicated loci may arise via one replication slippage. These observations agree with the findings of Butler et al. [5]. They have suggested that duplications of Y-STR markers might arise from a first dupli- cated region somewhere else on the Y chromosome, which then occurred a mutation at a specific Y-STR locus over time through the gain or loss of a repeat unit to produce a “new” allele. However, four or five copies of alleles could be ob- served at DYS385a/b or DYS459a/b. Gene conversion occurs frequently between repeated sequences on the Y chromosome [10]. Therefore, gene conversion may also play an important role in the mutational dynamics of duplication [11, 16].