1.Analysis of HPRT1 gene variant and prenatal diagnosis for a Chinese pedigree with Lesch-Nyhan syndrome but no specimen from affected probands.
Ming TONG ; Qian LI ; Anping SUN ; Canming CHEN ; Suwei HU
Chinese Journal of Medical Genetics 2022;39(11):1243-1246
OBJECTIVE:
To carry out genetic testing and prenatal diagnosis for a Chinese pedigree with Lesch-Nyhan syndrome (LNS) but no specimen from the affected probands.
METHODS:
All affected individuals in this pedigrees were male and had deceased during childhood, with no biological specimen left. Based on their typical neurological dysfunction and tendency for self-mutilation, the diagnosis of LNS was suspected. Sanger sequencing was carried out to detect potential variant of the HPRT1 gene among female members from the pedigree. Following the identification of the pathogenic variant, prenatal diagnosis was provided for a high-risk fetus.
RESULTS:
The proband's mother and three other females were found to harbor heterozygous c.500_501delGGinsC (p.Arg167fs*23) variant of the HPRT1 gene, which was unreported previously. Prenatal diagnosis showed that the fetus was a male and had inherited the same pathogenic variant.
CONCLUSION
The c.500_501delGGinsC variant of the HPRT1 gene probably underlay the LNS in this pedigree. Above finding has provided a basis for prenatal diagnosis and genetic counseling for this pedigree.
Male
;
Female
;
Humans
;
Pregnancy
;
Lesch-Nyhan Syndrome/genetics*
;
Pedigree
;
Hypoxanthine Phosphoribosyltransferase/genetics*
;
Prenatal Diagnosis
;
China
;
Mutation
2.Genetic analysis of a Chinese pedigree with Lesch-Nyhan syndrome.
Dujuan WANG ; Jingjing ZHAO ; Juan TENG ; Wen LI ; Xiangyu ZHAO ; Lin LI
Chinese Journal of Medical Genetics 2023;40(6):723-726
OBJECTIVE:
To explore the genetic etiology for a Chinese pedigree affected with Lesch-Nyhan syndrome.
METHODS:
Members of the pedigree who had visited the Genetic Counseling Clinic of Linyi People's Hospital on February 10, 2022 were selected as the study subjects. Clinical data and family history of the proband were collected, and trio-whole exome sequencing (trio-WES) was carried out for the proband and his parents. Candidate variants were verified by Sanger sequencing.
RESULTS:
Trio-WES revealed that both the proband and his cousin brother had harbored a hemizygous c.385-1G>C variant in intron 4 of the HPRT1 gene, which was unreported previously. A heterozygous c.385-1G>C variant of the HPRT1 gene was also found in the proband's mother, grandmother, two aunts, and a female cousin, whilst all phenotypically normal males in his pedigree were found to have a wild type for the locus, which has conformed to an X-linked recessive inheritance.
CONCLUSION
The heterozygous c.385-1G>C variant of the HPRT1 gene probably underlay the Lesch-Nyhan syndrome in this pedigree.
Male
;
Humans
;
Female
;
Lesch-Nyhan Syndrome/genetics*
;
Pedigree
;
East Asian People
;
Heterozygote
;
Introns
;
Mutation