has material basis in germline mutation in SDHD autosomal recessive disease mitochondrial complex 2 deficiency, nuclear type 3 https://github.com/monarch-initiative/mondo/issues/4521 https://github.com/monarch-initiative/mondo/issues/9178 A an autosomal recessive caused by pathogenic variants in the SDHD gene, leading to dysfunction of mitochondrial complex II. Clinical features are variable and may include Leigh syndrome, cardiomyopathy, and other neurological and muscular manifestations. MEDGEN:1751884 mitochondrial complex 2 deficiency, nuclear type 3 mitochondrial complex II deficiency, nuclear type 3 UMLS:C5436934 SDHD-related Nuclear type mitochondrial complex II deficiency OMIM:619167 MONDO:0030937 GARD:0016430 MC2DN3 mitochondrial complex II deficiency, nuclear type