# Myopathy due to carnitine palmitoyltransferase II deficiency: updating genetic aspects of the first publication in Brazil

## TL;DR

This paper updates the genetic understanding of a rare muscle disorder first reported in Brazil in 1983.

## Contribution

The study identifies new genetic variants in a historically significant case of CPT II deficiency.

## Key findings

- Compound heterozygous pathogenic variants (p.Ser113Leu/p.Pro50His) were found in the CPT2 gene.
- The paper connects historical clinical findings with modern genetic analysis of CPT II deficiency.
- It provides updated insights into the genetic basis of myopathy caused by CPT II deficiency.

## Abstract

Carnitine palmitoyltransferase II (CPT II) deficiency is an autosomal recessive inherited disorder related to lipid metabolism affecting skeletal muscle. The first cases of CPT II deficiency causing myopathy were reported in 1973. In 1983, Werneck et al published the first two Brazilian patients with myopathy due to CPT II deficiency, where the biochemical analysis confirmed deficient CPT activity in the muscle of both cases. Over the past 40 years since the pioneering publication, clinical phenotypes and genetic loci in the
CPT2
gene have been described, and pathogenic mechanisms have been better elucidated. Genetic analysis of one of the original cases disclosed compound heterozygous pathogenic variants (p.Ser113Leu/p.Pro50His) in the
CPT2
gene. Our report highlights the historical aspects of the first Brazilian publication of the myopathic form of CPT II deficiency and updates the genetic background of this pioneering publication.