Familial Infertility With Mutations In Zp1

Objective Zona pellucida is a surrounding transmembrane outside mammal’s oocytes. It consists of glycoproteins secreted by oocytes and granulosa cells. ZP plays a vital role in fertilization (specifically in spawn-egg binding and in preventing polyspermia) as well as in early stage development of embryos in pre-implantational phase. This research majorly concerns a family with infertility potentially caused by ZP genes absence. Familial genetic analysis and mutation analysis of ZP genes are conducted to study aetiological agent of ZP developing obstruction of this infertile family and molecular genetic mechanics of ZP deletion.Method Collecting marriage information of nine family members from three generations; drawing genogram; extracting DNA from peripheral blood of all nine members; screening all exons of propositus’ zpl-4genes; sequencing and analyzing all nine members’zpl-4genes respectively; processing biological information of the discovered mutationed genes.Results(1) Drawing genograph from3previous generations to the next generation of the propositus Ⅲ-land Ⅲ-2(propositus’ parents) are consanguineous marriage.Abnormal phonotype (infertility) concentrates in generation Ⅳ---Ⅳ-1,3(propositus),4, and5. Ⅳ-6and7haven’t married. Ⅳ-2is the only one of this generation who has a descendant.(2) PCR analysis confirms that all seven members of Ⅳ generation except Ⅳ-2(four female infertility patient and two unmarried within one male) carry a deletion of8bps (TGGGAAAA) at gene zp-1exon7c.1169. The rest three members (Ⅱ-1, Ⅲ-3, and Ⅳ-2) who have birthhistory have a loss of heterozygosity. The deletion will trigger appearance of terminator in advance.(3) The patient of family (Ⅳ-5) got COH and roe collection, we found that3oocytes have no zona pellucida.(4) Thus coded amino acid mutate from638aa to428aa. The37aa appear after mutation are newly coded amino acid.Conclusion Partially deletion of zp1causes ZP dysgenesis, therefore resulting ZP absence infertility. This mutation has abnormal clinical feature only if homozygous deletion appears. Inheritance pattern of this genetic infertility is an autosomal recessive inheritance.