Mutational analysis of WT1 and PLCE1 in three Chinese families with steroid-resistant nephrotic syndrome / 中华肾脏病杂志

ABSTRACT

Objective To examine mutations in the WT1 and PLCE1 gene in three Chinese families with autosomal recessive steroid-resistant nephrotic syndrome (SRNS) once mutations in NPHS2 had been excluded. Methods Peripheral blood samples were collected for genetic analysis from three probands of three Chinese families and their parents, and two probands' siblings, and 50 adult volunteers with normal urinalysis. Genomic DNA was isolated from peripheral blood leucocytes. Ten exons and exon-intron boundaries of WT1, and 31 exons and exon-intron boundaries of PLCE1 were amplified by polymerase chain reaction (PCR). Mutational analysis was performed by DNA sequencing directly and RFLP (restriction fragment length polymorphism) and/or PCR. Results No mutation in both WT1 and PLCE1 was identified in three probands from three Chinese families with autosomal recessive SRNS. However, three variants of WT1, 126C>T, ⅣS5-64A>G and 903A>G, and 13 variants of PLCE1, -134A>G, 810T>C, 960G>A, ⅣS11-28C>G, ⅣS15+26A>C, 4724G>C, ⅣS20+40C>T, ⅣS21+64G>A, ⅣS22-26T> A, 5320C>T, 5780A>G, ⅣS27+24A>G and ⅣS31 +48_49insT, were detected in three probands and some controls, indicating that all these variants were gene polymorphisms. WT1 polymorphism ⅣS5-64A>G, and PLCE1 polymorphism ⅣS22-26T>A were novel. Conclusion All the encoding exons and exon-intron boundaries of both WT1 and PLCE1 in three probands are examined, and no causative mutations in WT1 and PLCE1 axe found, suggesting that mutation in WT1 and PLCE1 genes is not a major cause of the Chinese families with autosomal recessive SRNS.