PREIMPLANTATION GENETIC DIAGNOSIS GLYCOGEN STORAGE DISEASE TYPE VI

Tiến Sang Triệu1, , Văn Khoa Trần1, Văn Phong Nguyễn1, Thế Sơn Trịnh2, Thanh Tùng Nguyễn2
1 Bộ môn Sinh học và Di truyền Y học, Học viện Quân y
2 Viện Mô phôi và Lâm sàng Quân đội, Học viện Quân y

Main Article Content

Abstract

Glycogen storage disease type VI (GSD6; OMIM#232700), also known as Hers disease, is an autosomal recessive genetic disorder with an incidence of approximately 1 in 1,000,000 people worldwide. The disease is characterized by impaired glycogen degradation function in the liver, resulting from abnormalities in the PYGL gene that encodes for the enzyme phosphorylase - an essential enzyme in glycogenolysis. Individuals with the disease typically present early with symptoms such as hepatomegaly, developmental delay, and hypoglycemia… Disease prevention has become feasible due to pre-implantation genetic diagnosis (PGD), allowing couples carrying variant to have healthy children.   


Objectives: Report on Pre-Implantation Genetic Diagnosis of Glycogen Storage Disease Type VI (GSD6).


Materials and methods: Based on the results of NGS sequencing of the affected son, Sanger sequencing was performed to identify the disease-causing variant in the blood samples of the father, mother, and child, along with 07 blastocyst biopsy samples from the couple. Additionally, linkage analysis using STR was conducted to provide the diagnostic results.


Results: Pre-implantation genetic diagnosis for Glycogen Storage Disease type VI (GSD6) was successfully performed on a couple who had previously given birth to an affected child. Results: Two embryos were normal and did not carry the disease-causing variant; one embryo carried the variant PYGL: c.1334T>C (p.Leu445Pro), one embryo carried a deletion variant spanning exon 14 to exon 17 of the PYGL gene, and three affected embryos.

Article Details

References

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