Expanding the Phenotype of the Founder South Asian Mutation in the Nuclear Encoding Mitochondrial RMND1 Gene

Mitochondrial disorders have a wide variability in the phenotype. A 10-mo-old girl presented with a severe phenotype of multisystem involvement due to an uncommon mitochondrial disease. Mutations in the RMND1 gene of nuclear DNA were identified on next generation sequencing. This mutation results in combined oxidative phosphorylation deficiency -11 (OMIM #614922) of the respiratory chain complex. So far in South Asia, patients of this disorder have been reported only from Pakistan and Bangladesh.

In addition to the features reported in other patients of South Asia with the same mutation at c.1349G>C, index patient from India had hyperaldosteronism, long QT interval but no deafness.

Thus, to conclude, this report emphasizes the diagnostic value of FGF21 assay in this disorder. It extends the phenotype associated with the founder mutation in RMND1 gene in patients from South Asia.