J Genet Med.  1998 Mar;2(1):17-22.

Molecular characterization and Prenatal Molecular Evaluation of three fetuses in four unrelated Korean families with Lesch-Nyhan syndrome

• Yoo HW
• Kim GH

Abstract

The Lesch-Nyhan syndrome which is caused by the deficiency of hypoxanthine guanine phosphoribosyltransferase is an X-linked recessive disorder characterized by hyperuricemia, choreoathetosis, mental retardation and compulsive self-injurious behavior. Clinical management of the patients with the Lesch-Nyhan syndrome is frustrating and requires burdensome medical treatment since it cripples the patient and shortens the life span by progression of neurological symptoms, but there are no cures or measures for relieving relentless natural course of the disease yet. Therefore, prenatal diagnosis of the affected fetus is important in genetic counselling for the family at high risk. In this study, four different mutations in the HPRT gene of four probands have been identified in four unrelated families; K215X, Q109X, nt.631 A, and nt.289 GT. Two mutations among them altered restriction enzyme sites; SpeI for Q109X and MaeI for nt.289 GT. Based on their molecular defects, prenatal diagnoses of 3 the fetuses were successfully made between ninth and eleventh week of gestation by polymerase chain reaction(PCR), restriction digestion and DNA sequencing using cDNA obtained from chorionic villus samples (CVS). We predicted the outcome of all fetuses prenatally. Among the three fetuses two were male and one was female according to the identification made by PCR amplification of the sex determining region of the Y chromosome(SRY) gene. Each carried a wild type allele for the corresponding mutant allele. They were also tested postnatally for the mutations to be unaffected.

Keyword

Lesch-Nyhan syndrome; HPRT gene; Prenatal diagnosis; Mutation

MeSH Terms

Alleles
Chorionic Villi
Digestion
DNA, Complementary
Female
Fetus*
Humans
Hyperuricemia
Hypoxanthine Phosphoribosyltransferase
Intellectual Disability
Lesch-Nyhan Syndrome*
Male
Polymerase Chain Reaction
Pregnancy
Prenatal Diagnosis
Self-Injurious Behavior
Sequence Analysis, DNA
DNA, Complementary
Hypoxanthine Phosphoribosyltransferase