Disease relevance of HYLS1

• Holoprosencephaly and polydactyly: a possible expression of the hydrolethalus syndrome [1].
• Clinical overlap with lethal acrodysgenital dwarfism (Smith-Lemli-Opitz syndrome type II) and hydrolethalus syndrome is discussed [2].
• The phenotype is consistent with the hydrolethalus syndrome, although holoprosencephaly has not previously been seen in this condition [1].
• The name hydrolethalus syndrome (hydramnios, hydrocephalus, lethality) may be of help in this [3].
• Hydrolethalus syndrome is a rare autosomal recessive (AR) disorder characterized by polyhydramnios, CNS abnormalities, cleft lip/palate, micrognathia, and polydactyly [4].

High impact information on HYLS1

• Hydrolethalus syndrome is caused by a missense mutation in a novel gene HYLS1 [5].
• The HYLS1 gene shows alternative splicing and the transcript is found in multiple tissues during fetal development [5].
• In situ hybridization shows spatial and temporal distributions of transcripts in good agreement with the tissue phenotype of HLS patients [5].
• The linkage disequilibrium (LD) and haplotype analyses of single nucleotide polymorphism (SNP) markers helped to further restrict the HLS locus to 476 kb between genes PKNOX2 and DDX25 [5].
• We believe other similar cases with a trisomy 13 phenotype but normal chromosomes may also have the hydrolethalus syndrome [1].

Chemical compound and disease context of HYLS1

• Hydrolethalus syndrome, in contrast to Smith-Lemli-Opitz syndrome, is not due to a defect in post-squalene cholesterol biosynthesis: a case report [6].

Biological context of HYLS1

• Two consecutive hydrolethalus syndrome-affected pregnancies in a nonconsanguinous black couple: discussion of problems in prenatal differential diagnosis of midline malformation syndromes [4].
• First-trimester diagnosis of hydrolethalus syndrome in a Chinese family [7].

Anatomical context of HYLS1

• In particular, colobomatous dysplasia and hypoplasia of the optic nerve seem to be typical of hydrolethalus syndrome [8].
• We present 2 unrelated fetuses with manifestations of both the hydrolethalus syndrome and the short rib-polydactyly syndrome, type Majewski [9].

Analytical, diagnostic and therapeutic context of HYLS1

• Hydrolethalus syndrome: report of an apparent mild case, literature review, and differential diagnosis [10].
• The prenatal diagnosis of hydrolethalus syndrome is presented on the basis of seven cases [11].

References