Sequence-specific transcription factor that binds gene promoters and activates their transcription. May play a role in the development of anterior structures, and in particular, the brain and facies and in specifying the identity or structure of hindlimb. Interacts with POU1F1 (PubMed:26612202). The disease is caused by variants affecting the gene represented in this entry. The gene represented in this entry is involved in disease pathogenesis. A chromosomal aberration involving the PITX1 locus results in LBNBG. Translocation t(5;18)(q31.1;q12.3). Additionally, two chromosome 5 deletions located 5'of PITX1 have been found in LBNBG patients. These structural variations cause altered expression of PITX1 in the forelimb via the activation of ectopic enhancers (PubMed:23022097). Belongs to the paired homeobox family. Bicoid subfamily.