Genetic polymorphism analyses of three novel X chromosomal short tandem repeat loci in the Xp22.3 region. (July 2020)

• Record Type: Journal Article
• Authors: Nishi, Takeki; Fukui, Kenji; Iwadate, Kimiharu
• Is Part Of: Legal medicine. Volume 45(2020)
• Publication Date: 2020-07
• Subjects: X-STR -- Short tandem repeat -- Japanese population -- Kinship testing -- Multiplex PCR; Medical jurisprudence -- Periodicals; Forensic Medicine -- Periodicals; Médecine légale -- Périodiques; Medical jurisprudence; Periodicals; 614.1
• DOI: 10.1016/j.legalmed.2020.101709
• Languages: English
• ISSNs: 1344-6223

Abstract

Highlights: We detected three novel STR loci in the Xp22.3 region. Haplotype analysis including nearby X-STR loci confirmed linkage disequilibrium between two groups of X-STR loci. We developed a multiplex PCR method based on the seven X-STR loci, including the three novel X-STR loci. The multiplex PCR system appears to be a useful tool for kinship testing and has potential for use in clinical settings. Abstract: X chromosomal short tandem repeats (X-STRs) can be useful for haplotype analysis in DNA testing, particularly for complex kinship testing or when one parent is absent. We searched downstream of four previously detected loci in the Xp22.3 region (LC149476, LC149479, LC149480, and LC149484) and detected and analyzed three novel short tandem repeats (STRs), LC317283, LC317284, and LC317285, with the repeat sequences TATAA, TTTA, and TATC, respectively. The forensic statistical values in Japanese subjects were confirmed to be noninferior to existing loci, with values for polymorphism information content, the power of discrimination in males (PDm), and the power of discrimination in females (PDf) of 0.5606–0.7448, 0.6078–0.7774, and 0.7990–0.9178, respectively. Haplotype analysis also revealed linkage disequilibrium between LC317283 and the four known loci (LC149476, LC149479, LC149480, and LC149484) and between two other novel loci (LC317284 and LC317285). Analysis of three family samples suggested that these STRs could be useful in complex kinship testing, so we developed an X-STR multiplex polymerase chain reaction (PCR) system for the seven loci and confirmed its ability to provide favorable amplification. We anticipate that the identified loci and developed multiplex PCR system will be beneficial to the field of forensic medicine.