Identification of a novel nonsense mutation and a missense substitution in the AGPAT2 gene causing congenital generalized lipodystrophy type 1

Abstract

Congenital generalized lipodystrophy (CGL) is an autosomal recessive disease characterized by the generalized scant of adipose tissue. CGL type 1 is caused by mutations in gene encoding 1-acylglycerol-3-phosphate O-acyltransferase-2 ( AGPAT2). A clinical and molecular genetic investigation was performed in affected and unaffected members of two families with CGL type 1. The AGPAT2 coding region was sequenced in index cases of the two families. The presence of the identified mutations in relevant parents was tested. We identified a novel nonsense mutation (c.685G>T, p.Glu229*) and a missense substitution (c.514G>A, p.Glu172Lys). The unaffected parents in both families were heterozygous carrier of the relevant mutation. The results expand genotype–phenotype spectrum in CGL1 and will have applications in prenatal and early diagnosis of the disease. This is the first report of Persian families identified with AGPAT2 mutations.

Highlights

► First diagnosis of congenital generalized lipodystrophy type 1 in Persian population. ► Molecular analysis identified a novel nonsense mutation and a missense substitution in the AGPAT2. ► The patients did not have diabetes mellitus or hyperinsulinemia. ► The mutations found are candidates for CGL screening. ► The results expand the knowledge about the genotype–phenotype correlations in CGL.