Researchers are homing in on the gene(s) that predisposespeople to the often deadly skin cancer, malignant melanoma.

A virtual consortium of researchers and institutions, led byLisa Cannon-Albright from the University of Utah MedicalSchool, has strong evidence linking the genetic susceptibilitylocus to the short arm of chromosome 9. In Friday's issue ofScience, the researchers reported results of a genetic linkageanalysis on 11 extended families, with 82 cases of melanomadiagnosed between the ages of 12 and 93. They found that a"cytogenetically detectable loss or rearrangement ofchromosome 9 occurs in approximately 46 percent of allmelanomas."

Cannon-Albright and her colleagues studied the inheritance ofgenetic markers that have already been linked to this area ofchromosome 9 by other studies that lend credence to itscancerous tendencies. "The genetic markers reside in acandidate region previously implicated by the presence ofhomozygous deletions in melanoma tumors and by thepresence of a germline deletion in one individual with eightindependent melanomas."

Although these data lend significant weight to the hypothesisthat chromosome 9 houses the melanoma susceptibility gene,other researchers, in studies back to 1989, point tochromosome 1 as the candidate. In fact, Alisa Goldstein of theNational Cancer Institute reported last week at the meeting ofthe American Society of Human Genetics that she and hercollaborators continue to find evidence for a melanoma locus onchromosome 1.

The incidence of melanoma has risen dramatically in recentyears. Today, more than 32,000 Americans contract the canceryearly, and of those about 8,000 die. But malignant melanomais not fatal if detected and treated early. "This is a diseasewhere we can clearly win," said Mark Green, an oncologist atthe Mayo Clinic and one of the scientists working on geneticanalyses. "Unraveling the genetics is extremely important."

-- Jennifer Van Brunt Senior Editor

(c) 1997 American Health Consultants. All rights reserved.