Identification and Characterization of Mutation Gene of Familiar Lymphedema

Familiar lymphedema is a genetic disorder disease and causes by dysfunction of vessel development, leading to swell of the extremities. In Taiwan, the mutation gene of familiar lymphedema is unclear. We have analyzed the mutation genes of members, whom are four patients and one health person from a four-generation family of familiar lymphedema by whole genome exon capture sequencing (WES). No mutation sites were identified in 11 familiar lymphedema related genes. We further analyzed the whole SNPs from these five members, two candidate mutation, Fam104BP63R and IGSF3S651I were identified. The functions of fam104b were unknown. One report was described the functions of igsf3, but it was not related to lymphedema. In this proposal, we will characterize the functions of fam104b and igsf3 on vessel development using transgenic zebrafish tg(fli:EGFP) to identify the mutation gene of familiar lymphedema. We will analyze the effects of these genes on vessel development by transient expression of Fam104BP63R and IGSF3S651I in tg(fli:EGFP). Knockout zebrafish fam104b and igsf3 orthologue genes in tg(fli:EGFP) by CRISPR-Cas9 technology will be used to identify the functions on vessel development. Rescue experiments by expression normal and mutated fam104b and igsf3 genes will be used to characterize the functions on vessel development. Finally, we will identify and characterize the regulation proteins and mechanisms of this mutation gene on vessel development by RNA-Seq, immunoprecipitation, LC-MS/MS and bioinformatics analysis. Collectively, we suggest that we will identify the mutation gene of familiar lymphedema in this family in Taiwan. We can detect the mutation gene of familiar lymphedema in clinical diagnosis and annotate the gene functions linking to this disease.