Scientists have identified six genes which may be involved in heightening the risk of contracting Alzheimer's disease. The chromosome 10 region appears to be involved in the process.
"There are a few genes that have been implicated in the development of early-onset Alzheimer's disease, but other than APOE, no genes have been found that increase risk for the more common, late-onset form of the disease," according to researcher Alison M. Goate at Washington University.
"The region of DNA identified in our study showed evidence of replication in four independent series of experiments. I haven't seen a putative risk factor show such consistent results since the e4 variant of the APOE gene was identified as a risk factor for the late-onset Alzheimer's disease more than 10 years ago," she added.
In the January issue of the American Journal of Human Genetics, Goate's team of researchers reports results of a scan of more than 1,400 single-nucleotide polymorphisms (SNPs) on chromosome 10 to home in on susceptibility genes for late-onset Alzheimer's disease.
Since most DNA do not make proteins, the majority of SNPs have no effect on DNA function or on health and disease. However, some SNP variants can cause major health problems. An example is APOE4, a common SNP in the apolipoprotein E gene that increases the risk for Alzheimer's disease.
"The region of DNA implicated in our study contains six genes. We don't know which of those genes is most likely to harbor this particular risk factor for Alzheimer's disease, but we're getting closer. We're now trying to nail down which one of these six genes is the most likely to be involved," Goate said.