Cloning and structural analysis of the human c-kit gene

Area of Science:

• Genetics and Molecular Biology
• Human Genomics
• Cell Signaling

Background:

• The c-kit receptor and its ligand are vital for embryogenesis, melanogenesis, and hematopoiesis.
• Previous studies in mice identified the White spotting and Steel loci as c-kit and its ligand, respectively.

Purpose of the Study:

• To determine the involvement of the c-kit proto-oncogene in human disease.
• To characterize the normal human KIT gene structure and genomic organization.

Main Methods:

• Isolation of seven overlapping lambda recombinants using fetal brain cDNA.
• Characterization of the human KIT gene, including transcript mapping and exon-intron structure analysis.
• Pulsed-field gel electrophoresis to determine gene linkage and localization.

Main Results:

• The human KIT gene transcript is 5230 bp, alternatively spliced, with 21 exons spanning over 70 kb.
• An alternative splice site was identified at the 3' end of exon 9.
• The KIT gene structure shares similarities with the CSF-1R gene, including a large first intron and similar exon-intron boundaries.
• KIT was linked to the platelet-derived growth factor receptor A gene on the same BssHI fragment.

Conclusions:

• The detailed characterization of the human KIT gene provides a foundation for further research.
• Understanding KIT's genomic structure and locus is essential for investigating its role in human diseases.
• These findings facilitate studies on KIT gene expression control and the identification of mutations or altered expression in disease states.