Objective: To identify the disease-causing gene in a four-generation Chinese family with 9 members affected with primary congenital lymphoedema (PCL, also known as Milroy disease).
Methods: Linkage analysis was performed with a few microsatellite markers flanking the candidate genetic loci for PCL, including 3 known genes associated with autosomal dominant PCL. For mutation analysis, VEGFR3 gene was sequenced with DNA from the proband. Direct DNA sequencing of exon 25 of the VEGFR3 gene was performed in all family members.
Results: The disease gene in the family was mapped to chromosome 5q35.3 with a maximum Lod score of 2.07. Direct DNA sequencing of VEGFR3 gene revealed a heterozygous C to T transition at nucleotide 3341, resulting in p.Pro1114Leu mutation. The p.Pro1114Leu mutation co-segregated with all affected individuals in the family.
Conclusion: This study identified a C3341T (p.Pro1114Leu) mutation in the VEGFR3 gene in a Chinese family with PCL, provided evidence that VEGFR3 mutation can cause PCL in Chinese.