Here we show that a holoprosencephaly mutation (P63R) interferes with the ability of TGIF to act as a corepressor for c-Jun and Smad2, suggesting that this holoprosencephaly mutation may lead to a general defect in the TGIF protein.
A missense mutation c.686C>T was found in the gene SIX3 of one patient, which did not differ from the accepted 20% of known HPE gene mutations among all HPE cases.