Affiliation:
1. University of Health Sciences
2. University of Sciences and Technologies of Masuku
3. Mother and Child University Hospital
4. Labor Für DNA-Analytik
Abstract
Abstract
Short tandem repeats (STRs) are repeating DNA sequences used in forensic human identity testing and the diagnosis of aneuploidies. Many STRs like Penta D and TPOX are used routinely for paternity tests, but these tests are not widely used in sub-Saharan Africa. The study population consisted of Gabonese families seeking a paternity test. After DNA extraction from the individuals collected by buccal swabs, we genotyped samples using a panel of 15 to 22 STRs. A total of 115 subjects from 39 families were included. Allele frequencies of the 22 STR loci were determined in unrelated Gabonese subjects. The most polymorphic loci were D21S11 and FGA, with 16 and 17 alleles, respectively, while D3S1358 and TH01 loci were less polymorphic, with 5 alleles. Deviations from Hardy-Weinberg equilibrium were only observed in the cases of TPOX, D3S1358, CSFPO and D7S820 loci. We report tri-allelic patterns that indicate aneuploidies at a combined frequency of 4% (4/115) with 3% for Penta D (1/35) and 3% for TPOX (3/102). Furthermore, we identified a new tri-allelic genotype 5-8-16 for the Penta D locus located on chromosome 21 in a healthy subject. In addition, we observed 3 tri-allelic variants of TPOX, located on chromosome 2, in healthy subjects, namely 8-10-11, 8-9-10, and 8-8-10. Our study revealed unsuspected polymorphic genetic mutations for the first time in Gabon that raise several questions about chromosomal disorders. Further population genetic studies are needed in Gabon to characterize these changes better, both qualitatively and quantitatively.
Publisher
Research Square Platform LLC
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