Mammalian Genome 1997;8(11):841-5 © Springer-Verlag New York Inc. 1997

Human and murine PTX1/Ptx1 gene maps to the region for Treacher Collins
syndrome.

Crawford MJ, Lanctot C, Tremblay JJ, Jenkins N, Gilbert D, Copeland N, Beatty B,
Drouin J

Laboratoire de genetique moleculaire, Institut de recherches cliniques de
Montreal (IRCM), Quebec, Canada.

Ptx1 belongs to an expanding family of bicoid-related vertebrate homeobox genes.
These genes, like their Drosophila homolog, seem to play a role in the
development of anterior structures and, in particular, the brain and facies. We
report the chromosomal localization of mouse Ptx1, and the cloning, sequencing,
and chromosomal localization of the human homolog PTX1. The putative encoded
proteins share 100% homology in the homeodomain and are 88% and 97% conserved in
the N- and C-termini respectively. Intron/exon boundaries are also conserved.
Murine Ptx1 was localized, by interspecific backcrossing, to Chr 13 within 2.6
cM of Caml. The gene resides centrally on Chromosome (Chr) 13 in a region
syntenic with human Chr 5q. Subsequent analysis by fluorescent in situ
hybridization places the human gene, PTX1, on 5q31, a region associated with
Treacher Collins Franceschetti Syndrome. Taken together with the craniofacial
expression pattern of Ptx1 during early development, the localization of the
gene in this chromosomal area is consistent with an involvement in Treacher
Collins Franceschetti Syndrome.

PMID: 9337397, UI: 98051903