Compound heterozygous Pkd1l1 variants in a family with two fetuses affected by heterotaxy and complex Chd.

Heterotaxy and congenital heart defects associated with pathogenic variants in the PKD1L1 gene (autosomal visceral heterotaxy type 8, MIM 617205) has been reported in only four individuals from three unrelated families. We describe a further family with two affected fetuses and novel compound heterozygous pathogenic variants in PKD1L1. PKD1L1 has been shown to function in the ciliary sensation of nodal flow at the embryo primitive node and in the restriction of NODAL signalling to the left lateral. plate mesoderm, mechanisms involved in the development of laterality in vertebrates. Individuals affected with this autosomal recessive condition have variable thoracic and abdominal situs. Features of CHD and other anomalies vary between and within families.