New Genetic Variant Linked to Rare Fat Distribution Disorder

Familial Partial Lipodystrophy Type 2 (FPLD2) is a rare genetic disorder characterized by abnormal fat distribution, often leading to severe metabolic complications like insulin resistance and dyslipidemia. It is primarily caused by mutations in the LMNA gene, which encodes lamin A/C, a crucial protein for nuclear structure and function. Identifying novel LMNA variants is essential for expanding our understanding of FPLD2's genetic basis and improving diagnostic accuracy.

The investigation successfully identified a novel missense variant in the LMNA gene, designated c.604G>C (p.Glu202Gln), which was found to segregate perfectly with the disease phenotype within the family. All four clinically affected individuals carried this specific variant in a heterozygous state, while it was entirely absent in all three unaffected family members. Affected individuals presented with characteristic FPLD2 symptoms, including severe insulin resistance (fasting insulin levels averaging 25-30 mIU/L compared to 5-10 mIU/L in controls), dyslipidemia (triglycerides often exceeding 300 mg/dL), and a distinctive pattern of partial lipoatrophy (loss of subcutaneous fat) in the limbs and gluteal regions, coupled with fat accumulation in the face and neck. The novel LMNA variant c.604G>C (p.Glu202Gln) demonstrated 100% penetrance within the studied family, being exclusively present in affected individuals and absent in unaffected ones, strongly establishing its pathogenic role in Familial Partial Lipodystrophy Type 2.