Childhood onset homozygous recessive GDAP1 (p.Pro231Leu) mutation in a 9-year-old puerto rican pediatric female with axonal Charcot-Marie-Tooth disease: A case report.

Charcot-Marie-Tooth disease (CMT) is a progressive hereditary neuromuscular neuropathy with pathology in the myelin sheath or the axon. CMT caused by mutations in the Ganglioside-induced differentiation associated protein 1 (GDAP1) gene has been described by a spectrum of phenotypic presentations. GDAP1 is a mitochondrial protein responsible for protecting neuronal bodies from oxidative stress. It is associated with axonal and demyelinating pathophysiology with recessive and dominant modes of inheritance.We describe a case of a 9-year-old Puerto Rican female with clinical and electrodiagnostic results compatible with an axonal sensory-motor neuropathy where a genetic test describes a homozygous GDAP1 missense mutation at the c.692C>T (p.Pro231Leu), previously undetected in a pediatric Latino patient. Mutations in GDAP1 have been previously described in Tunisian, Old Order Amish, European and Japanese families with varying modes of inheritance. To our knowledge, this homozygous variant presentation of the GDAP1 gene is the first to be described in a pediatric Puerto Rican patient without a family history of hereditary sensory motor neuropathy.

Familial Hyperckemia and Calf Hypertrophy Secondary to a Caveolin-3 Mutation.

ABSTRACT: Idiopathic hyperckemia has been described as persistent serum creatine kinase elevation at least 1.5 times the upper limit of normal in individuals with otherwise normal laboratory findings and neurological examination. This type of hyperckemia encompasses both sporadic and familial cases, which have been found to be asymptomatic or subclinical, presenting with mild symptoms, such as myalgias or cramps. Genetic causes of hyperckemia have been rarely described. The authors aim to describe a benign autosomal dominant condition caused by a rare mutation in the caveolin gene. Caveolin gene encodes for structural membrane proteins in muscle. The purpose of this article was to discuss the presentation, pathophysiology, and diagnosis of familial hyperckemia secondary to a relatively unknown mutation in caveolin-3 gene.