WP3674 - Tgif disruption of Shh signaling - Homo sapiens

Mutations in the Sonic Hedgehog (SHH) gene result in HPE in humans and mice, and the Shh pathway is targeted by other mutations that cause holoprosencephaly (HPE). HPE is a severe human genetic disease affecting craniofacial development of children. The TGIF1 gene maps to the HPE4, and the heterozygous loss of the TGIF1 mutations are associated with HPE, however mouse models have yet to explain how the inhibition of TGIF causes the genetic disease Holoprosencephaly. Using a conditional Tgif1 allele, Taniguchi, et al. showed that mouse embryos lacking both Tgif1 and the related Tgif2 have HPE-like phenotypes reminiscent of Shh null embryos.