Analysis of ALMS1 gene mutation and prenatal diagnosis in two pedigrees with Alstrom syndrome / 中华围产医学杂志

ABSTRACT

This article reported the genetic etiology of two pedigrees with Alstrom syndrome and the results of prenatal genetic diagnosis in the second pregnancies of the two pedigrees. The probands in the two pedigrees both had different degrees of visual abnormalities. The mothers of the two probands were pregnant again and received prenatal diagnosis in the First Affiliated Hospital of Zhengzhou University. Whole-exome sequencing and Sanger sequencing confirmed that the proband of pedigree 1 carried compound heterozygous variants of c.6103C>T(p.Gln2035*) and c.6430C>T(p.Arg2144*) in ALMS1 gene, and the parents were carriers. While the proband of pedigree 2 was found to carry compound heterozygous variants of c.9148_9149delCT(p.Cys3051Serfs*9) and c.12028delC(p.Leu4010Typfs*19) in ALMS1 gene and the parents were also carriers. Among these variants, c.6103C>T(p.Gln2035*), c.9148_9149delCT(p.Cys3051Serfs*9) and c.12028delC(p.Leu4010Typfs*19) were all de novo ones. Prenatal genetic detection confirmed the fetus of pedigree 1 carried c.6430C>T(p.Arg2144*) variant inherited from the father and the pregnancy was continued after genetic counselling, while the fetus of pedigree 2 was found to carry both of the same variants as the proband and the pregnancy was terminated.