A study population of 348 patients collected over more than 10 years with a large variety of congenital heart disease including heterotaxy was screened for variants in the ZIC3 gene.
Here we summarise our current understanding of ZIC3 function and describe the potential role ZIC3 plays in important signalling pathways and their links to heterotaxy.
Identified cytogenetic abnormalities ranged from large unbalanced translocations to smaller, kilobase-scale CNVs, including a rare, single exon deletion in ZIC3, a gene known to cause X-linked heterotaxy.
Longitudinal follow-up revealed that this family has X-linked heterotaxy due to a missense mutation, c.1048A>G(R350G), in the third zinc finger domain of ZIC3.
Patients with TGA (n = 169), double outlet right ventricle (DORV; n = 89), common atrioventricular canal (CAVC; n = 41), and heterotaxy (n = 54) underwent sequencing of ZIC3 exons.
Previously we mapped a locus for situs abnormalities in humans, HTX1, to Xq26.2 by linkage analysis in a single family (LR1) and by detection of a deletion in an unrelated situs ambiguus male (Family LR2; refs 2,3).
Previously we mapped a locus for situs abnormalities in humans, HTX1, to Xq26.2 by linkage analysis in a single family (LR1) and by detection of a deletion in an unrelated situs ambiguus male (Family LR2; refs 2,3).
The birth incidence of heterotaxy-spectrum malformations is significantly higher in males, but our previous work indicated that mutations within ZIC3 did not account for the male over-representation.
These results define the temporal and spatial requirements for Zic3 in node morphogenesis, left-right patterning and cardiac development and suggest the possibility that a requirement for Zic3 in node ultrastructure underlies its role in heterotaxy and laterality disorders.
We sought to develop a hypomorphic Zic3 mouse to model human heterotaxy and investigate developmental mechanisms underlying variability in cardiac phenotypes.