X-linked and autosomal genes controlling mouse alpha-galactosidase expression.

Area of Science:

• Genetics and genomics
• Biochemistry
• Developmental biology

Background:

• Alpha-galactosidase is an enzyme encoded by the Ags gene.
• Gene linkage and mapping are crucial for understanding genetic organization.
• Developmental expression of enzyme activity can vary and be genetically controlled.

Purpose of the Study:

• To confirm the chromosomal location of the mouse alpha-galactosidase structural locus (Ags).
• To determine the precise genetic map position of Ags on the mouse X chromosome.
• To characterize a variation in alpha-galactosidase developmental expression and its genetic basis.

Main Methods:

• Analysis of F2 and backcross progeny to establish gene linkage.
• Genetic mapping using known marker loci (Hq, Bn, Ta, Mo) on the X chromosome.
• Characterization of enzyme activity variation in recombinant inbred mouse lines.

Main Results:

• The Ags locus was confirmed to be X-chromosome linked.
• The genetic order centromere-Hq-Bn-Ta-Mo-Ags was established, with Ags 9 centimorgans from Mo.
• A distinct autosomal trait influencing alpha-galactosidase developmental expression was identified and characterized in specific recombinant inbred lines, appearing to segregate as a single major locus.

Conclusions:

• The structural gene for mouse alpha-galactosidase (Ags) is located on the X chromosome.
• A separate genetic locus, inherited autosomally, controls variations in the developmental expression of alpha-galactosidase activity in mice.