Hydrolethalus syndrome protein 1 (IPR026227)

Short name: HYLS1

Overlapping homologous superfamilies


Family relationships



Hydrolethalus syndrome (HLS) is an autosomal recessive lethal malformation syndrome, leading to still-birth, or death shortly after birth. The syndrome is characterised by hydrocephaly, with absent upper midline structures of the brain, micrognathia and polydactyly. A variety of other features (including cleft lip or palate, club feet, anomalies of the ears, eyes and nose, a keyhole-shaped defect in the occipital bone, abnormal genitalia, and congenital heart and respiratory organ defects) have also been observed in affected individuals [PMID: 15843405]. Characterisation of the underlying molecular defect is important, as it could both expose new molecular pathway(s) essential for normal human development and provide new insights into foetal malformation syndromes.

The critical HLS region has been defined to a 476 kb interval using cases from 30 Finnish HLS families [PMID: 15843405]. Within this region, sequence analysis has revealed a point mutation in a novel gene (termed HYLS1) that results in substitution of a well-conserved Asp by Gly in a predicted polypeptide of unknown function. The HYLS1 product does not share similarity with known polypeptides, but the wide tissue-expression-pattern of the gene is consistent with it being essential for early development of the human foetus [PMID: 15843405].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.