Genetic testing and prenatal diagnosis of 64 pedigrees with autosomal dominant polycystic kidney disease / 中华肾脏病杂志

ABSTRACT

Objective:To detect and analyze the gene variation types of 64 unrelated pedigrees affected with autosomal dominant polycystic kidney disease (ADPKD), and explore the detection efficiency of multiple gene analysis techniques and variation characteristics.Methods:It was a cross-sectional study. The clinical data of 64 pedigrees with ADPKD from Nephrology Department or Genetic and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University from December 2017 to August 2020 were retrospectively analyzed. The blood samples of probands and other family members were collected. Genetic analysis was carried out by next generation sequencing, and suspected mutations were verified by multiplex ligation-dependent probe amplification, or long-range PCR combined with Sanger sequencing. Prenatal diagnosis for high-risk fetuses was performed by fetal villi or amniotic fluid cells after genotyping without maternal genomic DNA contamination.Results:Among detected 64 pedigrees, 57 pedigrees (89.06%) had genetic variants in PKD1/PKD2. A total of 49 pathogenic/likely pathogenic variants in PKD1/PKD2 were identified in 51 pedigrees (79.69%), including 14 nonsense variants (28.57%), 14 frameshift variants (28.57%), 11 missense variants (22.45%), 5 splicing variants (10.20%) and 5 deletion variants (10.20%). Of these variants, 87.76% (43/49) were in PKD1 and 12.24% (6/49) were in PKD2. Totally, 14 novel variants in PKD1/ PKD2 were identified, including 7 frameshift variants, 3 splicing variants, 2 nonsense variants, 1 deletion variant and 1 missense variant, of which 11 variants were in PKD1 and 3 variants were in PKD2. Twenty high-risk fetuses from 17 pedigrees received prenatal diagnosis, in whom 6 fetuses had PKD1 variation, and other 14 fetuses had no PKD1/ PKD2-genetic variation. Conclusions:The combination of next-generation sequencing, multiplex ligation-dependent probe amplification, and long-range PCR combined with Sanger sequencing can be helpful for rapid, efficient and accurate genetic diagnosis of ADPKD pedigrees. Point mutations are the most common types in PKD1/PKD2. Fourteen novel variants in PKD1/PKD2 extend its pathogenic variant spectrum and can provide basis for genetic counseling and prenatal diagnosis of ADPKD pedigrees.