Genetic screening and prenatal diagnosis in 18 high-risk families with 21-hydroxylase deficiency / 中华医学遗传学杂志

ABSTRACT

OBJECTIVE@#Genetic screening and prenatal diagnosis was performed in eighteen families with high risk of 21-hydroxylase deficiency (21-OHD) to provide valuable information for genetic counseling in these affected families.@*METHODS@#First, multiplex ligation-dependent probe amplification (MLPA) combined with nested-PCR based Sanger sequencing was used to detect CYP21A2 gene mutations in probands and their parents of eighteen families, with seven probands had been dead. Second, paternity test was applied to exclude the possibility of maternal genomic DNA contamination, and fetal prenatal diagnosis is based on the mutations found in proband or parents of the family.@*RESULTS@#Ten mutations were identified in these eighteen families, including large fragment deletion, I2G, E3del8bp, I172N, V281L, E6 cluster, L307Ffs, Q318X, R356W and R484Pfs. All probands were caused by homozygous or compound heterozygous mutations of CYP21A2 gene and their parents were carriers. By comparing short tandem repeat sites contamination of maternal genomic DNA was not found in fetal DNA. Prenatal diagnosis showed that five fetus were 21-OHD patients, four fetus were carriers and the other nine fetus were normal.@*CONCLUSION@#CYP21A2 gene mutation is the etiology of 21-OHD. Genetic testing of CYP21A2 could assist physicians in 21-OHD diagnosis and provided genetic counseling and prenatal diagnosis for parents who are at risk for having a child with congenital adrenal hyperplasia.