Ethnicity

Naomi Johnson 

"Ethnicity May Influence Antibody Genes: Immunity-Related DNA Sections Could Vary Depending On Ethnicity"

4/18/13

Our nation has discovered that a good number of our antibody genes, how well they operate and, potentially, what they fight off, actually vary from person to person. That means even though drugs, treatments and vaccinations are designed to treat whole populations, our response to them could be individualistic. These scientists have also found ethnicity may influence immunity. Scientists have long known that our IGH-chain locus is our most prolific producer of the 50-plus varied and diverse antibody-encoding genes that our B cells use to fight off infections and diseases.But thanks to new data-mining technology, this is the first study to radically refine and, until now, roughly-piecemealed genomic map of the human IGH-chain locus.

They have discovered that a good number of our antibody genes, how well they operate and, potentially, what they fight off, actually vary from person to person. That means even though drugs, treatments and vaccinations are designed to treat whole populations our response to them could be individualistic.

After completely sequencing the immensely repetitive DNA in the human genome’s one million nucleotide-long immunoglobulin heavy (IGH)-chain locus, these scientists have also found ethnicity influences immunity.

“Time will confirm the extent to which this is true. But we’ve found that sections of the IGH-chain locus’ DNA sequence are either missing or inserted into a person’s genome, and this could vary depending on ethnicity,” explains Corey Watson.

A postdoctoral researcher at the Mount Sinai School of Medicine in New York, Watson completed his doctoral studies under the supervision of SFU biologist Felix Breden who leads this research project. Watson and Breden still collaborate on research.

Scientists have long known that our IGH-chain locus is our most prolific producer of the 50-plus varied and diverse antibody-encoding genes that our B cells use to fight off infections and diseases.But thanks to new data-mining technology, this is the first study to radically refine and, until now, roughly-piecemealed genomic map of the human IGH-chain locus as said earlier.

“Because this is the most complete version of a human’s IGH sequence,” says Watson, “our data has been integrated into the official human genome project assembly.”

Using a single chromosome of an individual, the latest study sequences all possible antibody-encoding genes in our IGH-chain locus. It also identifies 11 possible large DNA insertions and deletions of antibody-encoding genes in the region that determine our antibody gene count/diversity and, in some cases, have been implicated in disease susceptibility.

The scientists uncovered the link between antibody makeup and ethnicity when they screened the chromosomes of 425 people of Asian, African and European descent for several DNA insertions and deletions.