L2HGDH and L-2-hydroxyglutaric aciduria: Another gene among the top hits, L2HGDH, is involved in L-2-hydroxyglutaric aciduria (L2HGA), a rare autosomal recessive disorder clinically characterized by a mild psychomotor delay followed by progressive cerebellar ataxia and moderate to severe intellectual disability and a tendency to the development of malignant brain tumors [75].