The current study aims to analyze the length polymorphisms in sequence-tagged-site (STS) sY1291 of the Y chromosome in Vietnamese men of infertile couples. All 322 DNA samples were amplified with the sY1291 primer by the quantitative fluorescent polymerase chain reaction (QF-PCR) assay. DNA sequencing technique was employed to evaluate the accuracy of QF-PCR results. The study showed 273 out of 322 DNA samples had the presence of STS sY1291, accounted for 84.78%. The QF-PCR results showed that there were various lengths in STS sY1291: 507 bp, 512 bp, 523 bp and 527 bp. The most prevalent length in STS sY1291 was 507 bp (87.5%), the others were 512 bp (4.8%), 523 bp (4.8%) and 527 bp (2.9%). We found that the observed length polymorphisms derived from differences in the number of mononucleotide Thymine (T) repeats in its structure. It stretched from 22 T to 39 T. DNA sequencing results identified that the number of mononucleotide T repeats causes these polymorphisms. However, the pair-wise alignment between the obtained and reference sequence was 77%. It can be seen that the length polymorphisms in STS sY1291 observed in QF-PCR results was accurate but it is still difficult to sequence fragments with mononucleotide repeats.
Dr. Cao Thi Tai Nguyen, was born in Quy Nhon, Vietnam. She received the B.A. degree in Biology from Quy Nhon University, in 2004, and the M.Sc. and Ph.D. degrees in Biotechnology from Can Tho University, Vietnam, in 2010 and 2019, respectively. She joined Tai Furniture Company, Vietnam, as a secretary and helped ELICs volunteer teachers from 2005 to 2006 at Quy Nhon University. Since March 2006, she has been a lecturer at Department of Biology – Genetics, Can Tho University of Medicine and Pharmacy, Vietnam. My current research interests include molecular biology, cell biology and genetics.