Novel compound heterozygous mutations in WEE2 causes female infertility and fertilization failure

Purpose To identify the disease-causing gene in a family with female infertility and fertilization failure. Methods Whole-exome sequencing and Sanger sequencing were used to identify the disease-causing gene in a female with infertility and fertilization failure. Subcellular localization and western blot analysis were used to check the effect of mutations. Results We identified novel compound heterozygous mutations c.598C>T (p.Arg200Ter) and c.1319G>C (p.Trp440Ser) in WEE2 gene in a female with infertility and fertilization failure. The p.Arg200Ter mutant WEE2 gene produce truncated protein and mainly located in the nucleus, the same as the wild protein, while the p.Trp440Ser mutant WEE2 proteins are located in the nucleus and cytoplasm and the expression level of p.Trp440Ser mutant WEE2 protein is reduced significantly compared with that of wild-type WEE2. Conclusions We discovered novel compound heterozygous mutations c.598C>T (p.Arg200Ter) and c.1319G>C (p.Trp440Ser) in WEE2 gene in a female whose oocytes could not form pronucleus after intracytoplasmic sperm injection (ICSI). Moreover, mutations in WEE2 gene affect the normal function of WEE2 proteins and cause fertilization failure.