Niemann-Pick disease type C: analysis of 7 patients

Rare Loss-of-Function Variants in NPC1 Predispose to Human Obesity

Some Shanghai Clinical Center f a role of Niemann-Pick type C1 (NPC1) for obesity traits. However, whether the loss-of-function mutations in NPC1 cause adiposity in humans remains unknown. We recruited 25 probands with rare autosomal-recessive Niemann-Pick type C (NP-C) disease and their parents in assessment of the effect of heterozygous NPC1 mutations on adiposity. We found that male NPC1^+/- carriers had a significantly higher BMI than matched control subjects or the whole population-based control subjects. Consistently, male NPC1^+/- mice had increased fat storage while eating a high-fat diet. We further conducted an in-depth assessment of rare variants in the NPC1 gene in young, severely obese subjects and lean control subjects and identified 17 rare nonsynonymous/frameshift variants in NPC1 (minor allele frequency <1%) that were significantly associated with an increased risk of obesity (3.40% vs. 0.73%, respectively, in obese patients and control subjects, P = 0.0008, odds ratio = 4.8, 95% CI 1.7-13.2), indicating that rare NPC1 variants were enriched in young, morbidly obese Chinese subjects. Importantly, participants carrying rare variants with severely damaged cholesterol-transporting ability had more fat accumulation than those with mild/no damage rare variants. In summary, rare loss-of-function NPC1 mutations were identified as being associated with human adiposity with a high penetrance, providing potential therapeutic interventions for obesity in addition to the role of NPC1 in the familial NP-C disease.

Unusually prominent horizontal gaze palsy in a case of Niemann-Pick type C disease

Niemann-Pick Type C disease (NPC) is a rare inherited metabolic disorder characterized by lipid accumulation and systemic manifestations due to multiple organ involvement. Only a few cases of NPC have been reported so far from India. Varying presentations and often lack of access to complex diagnostic tests have leaded to initial misdiagnosis on few occasions. We here report a provisionally diagnosed case of NPC with prominent horizontal gaze palsy along with characteristic vertical gaze palsy and normal findings on microscopic examination of skin biopsy specimen.