has material basis in germline mutation in FGF16 syndactyly type 8 https://github.com/monarch-initiative/mondo/issues/4521 https://rarediseases.info.nih.gov/diseases/3559/metacarpals-4-and-5-fusion https://www.malacards.org/card/metacarpal_4_5_fusion fusion of metacarpals 4 and 5 GARD:0003559 OMIM:309630 FGF16 non-syndromic syndactyly SCTID:715442006 metacarpal 4-5 fusion MEDGEN:333392 MF4 MONDO:0010669 DOID:0111813 metacarpal 4-5 fusion, X-linked recessive UMLS:C1839728 non-syndromic syndactyly caused by mutation in FGF16 Syndactyly type 8 is a rare, genetic, non-syndromic, congenital limb malformation characterized by unilateral or bilateral fusion of the fourth and fifth metacarpals with no other associated abnomalities. Patients present shortened fourth and fifth metacarpals with excessive separation between their distal ends, resulting in marked ulnar deviation of the little finger and an inability to bring the fifth finger in parallel with the other fingers. MESH:C564100 metacarpals 4 and 5 fusion Orphanet:2498 icd11.foundation:577712860 non-syndromic syndactyly