Chromosomal assignment of equine genes involved in the development of skeletal, gastrointestinal, cardiovascular and nervous system.

The research article presents a chromosomal assignment of certain equine genes involved in the development of skeletal, gastrointestinal, cardiovascular and nervous systems. These genes such as GLI3, SALL1, PAX6, and IL1RAPL2 have been linked to various disorders or malformation syndrome, if found mutated.

GLI3 Encoded Protein

• The GLI3 encoded protein belongs to the C2H2-type zinc finger proteins of the GLI-Kruppel family. These are DNA-binding transcription factors and mediators of the Sonic hedgehog (Shh) signaling which play a crucial role in embryogenesis.
• Any mutations in the GLI3 gene can lead to various disorders that affect limb and craniofacial development in humans. For example, Greig cephalopolysyndactyly syndrome, Pallister-Hall syndrome, preaxial polydactyly type IV, and postaxial polydactyly types A1 and B are some of the disorders linked to mutations in this gene.
• Large deletions and translocations have also been found in patients with Greig cephalopolysyndactyly syndrome.

SALL1 Gene Product

• The SALL1 gene product is a zinc finger protein which functions as a transcription factor. It contains four highly conserved C2H2 double zinc finger domains.
• Functional polymorphisms of the SALL1 gene in humans can cause Townes–Brocks syndrome, a rare autosomal dominant malformation syndrome characterized by anal, renal, limb, and ear anomalies.
• Exon 2 of the human SALL1 gene is found to be the most likely mutation site for Townes–Brocks syndrome

Paired Box Gene 6 (PAX6)

• Paired box gene 6 (PAX6) plays an important role in the development of sensory organs, and neural, epidermal and ectodermal tissues.
• Mutations of the PAX6 gene can cause a wide array of defects in ocular tissue. These include aniridia, a lack of the colored part of the eye, or coloboma, a condition where normal tissue in or around the eye is missing.
• In two aniridia pedigrees, the disease has been linked with chromosomal breakpoints located near the PAX6 locus.

IL1RAPL2 Gene

• The IL1RAPL2 gene produces a protein that is a member of the interleukin 1 receptor family. This protein is closely related to interleukin 1 receptor accessory protein-like 1 (IL1RAPL1). Both genes are located at a region on the X chromosome.
• This region is associated with X-linked non-syndromic mental retardation in humans.