H syndrome (OMIM #612391) is a rare autosomal recessive disorder, first described by Molho-Pessach I et al i [1] for the common clinical features of hyperpigmentation, hypertrichosis, hepatosplenomegaly, hearing loss, heart anomalies, hypogonadism, low height, hyperglycemia (insulin-dependent diabetes mellitus), and hallux valgus/flexion contractures. To date there have been only about 100 patients confirmed to have H syndrome globally.[2] It is caused by mutations in SLC29A3 (10q22.2) (encoding human equilibrative nucleoside transporter, hENT3). More than 20 mutations have been identified in the SLC29A3 gene in affected H syndrome, with G437R being the most commonly described.[3] Mutation analysis of SLC29A3 in our patient revealed a c.1087C > T missense mutation in exon 6. [Extracted from the article]