Identification and characterization of a case of mild familial partial lipodystrophy in a carrier of a LMNA p.Arg582Leu variant

Abstract

Laminopathies are a group of rare disorders caused by mutations in the Lamin A/C gene located on human chromosome 1q22. The LMNA gene encodes Lamin A and C that are components of the nuclear lamina in most differentiated cells. Furthermore, Lamin A/C plays a pivotal role in cell differentiation. LMNA mutations affect mainly mesenchymal tissues (muscle, bone, and adipose tissue), although they sometimes also affect the nervous system to varying degrees. There are several clinical presentations of laminopathies, as different LMNA mutations are responsible for different phenotypes, including lipodystrophy, skeletal muscle dystrophy, and cardiomyopathy [1]. LMNA lipodystrophy can be classified as partial, or generalized, based on the extent of atrophy of the subcutaneous fat. The most well-known and common form of LMNA lipodystrophy is familial partial lipodystrophy type 2 (FPLD2) that is transmitted as an autosomal dominant disorder. FPLD2 is characterized by subcutaneous adipose tissue loss from the trunk, buttocks and limbs and muscular pseudohypertrophy which is usually accompanied by accumulation in the face, neck and abdominal viscera, and is frequently associated with metabolic and cardiovascular complications. The reported prevalence is 1 case per 100,000 inhabitants in Europe, but it is likely largely underestimated. We herein report the case of a female patient who was occasionally found to harbor a mutation compatible with FPLD2.