
Sheep Genes
May Aid Medical ResearchersBy David Elstein September 16, 2002A mutated sheep gene discovered by
Agricultural Research Service and
Duke University scientists could help other
researchers "fill in the blanks" in areas of the human genome and
also might provide clues to the role of certain genes in human health. A report
on the discovery appears in the current issue of the journal Genome Research. The mutated gene, named callipyge, was found in a flock of sheep in
Oklahoma in the early 1980s. Some of these sheep had large muscling in their
loins and legs. Research revealed that the only sheep with the abnormal
muscling were those which had inherited a normal copy of a specific gene from
their mother, but a mutated copy of that same gene from their father. This
inheritance pattern is termed "paternal polar overdominance," and the
case of the Oklahoma sheep was the first known example of this condition in
mammals. Duke University cancer researchers believe the discovery of this mutated
gene may help them in their research. The Duke group has been working on
identifying "imprinted genes"--genes that work differently than
normal genes because the expression of the gene's product depends on which
parent the gene copy was inherited from. The Duke group is interested in
"imprinting" as it relates to human cancer. Duke cancer researcher Randy Jirtle also wants to find out how genes in this
region of the sheep genome might be reflected in humans. The approach of
aligning the sheep sequence of this specific region to the human genome to
possibly identify a previously unknown human gene could aid efforts in other
imprinted regions of importance to human medicine. According to ARS geneticist Brad Freking of the Roman L. Hruska U.S. Meat
Animal Research Center (MARC) in Clay
Center, Neb., this research shows the value of obtaining genomic sequences of
more agricultural species to align with the human genome in the search for
novel genes. Alignment of genomic sequences from several species could help
identify important genetic regions not previously recognized in the human
genome. This is especially true for regions containing mutations in livestock
that have a major impact on the animal, such as the callipyge mutation
discovered at MARC. ARS is the U.S. Department of
Agriculture's chief scientific research agency. Story contacts U.S. Meat Animal Research Center U.S. Department of Agriculture |