Journal article Open Access

Mutations in MCT1 cDNA in patients with symptomatic deficiency in lactate transport

Merezhinskaya, Natalya; Fishbein, William N.; Davis, John I.; Foellmer, John W.

We identified 5 patients with subnormal erythrocyte lactate transport plus symptoms and signs of muscle injury on exercise and heat exposure. All had transport rates below the 95% envelope for normals. Three cases had rates 40–50% of mean normal. One was found to have a missense mutation in monocarboxylate transporter 1 (MCT1), the gene for the red cell lactate transporter (also expressed in skeletal muscle), at a conserved site, which was not mutated in a cohort of 90 normal humans. The other 2 cases had a different missense mutation (at a nonconserved site), which was also not mutated in the normal cohort. All 3 patients were heterozygotes. We presume that these mutations are responsible for their subnormal lactate transport, and hence their muscle injury under environmental stress; homozygous patients should be more seriously compromised. The other 2 cases had lactate transport rates 60–65% of mean normal, and their MCT1 revealed a third mutation, which proved to be a common polymorphism in the normal cohort. These 2 patients may be physiologic outliers in lactate transport, with their muscle damage arising from some other genetic defect.

Files (315.2 kB)
Name Size
article.pdf
md5:3e2936b25f677206fad32aac69f4f119
315.2 kB Download
64
92
views
downloads
Views 64
Downloads 92
Data volume 29.0 MB
Unique views 64
Unique downloads 90

Share

Cite as