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Name: Regina W.
Status: Other
Age: 40s
Location: N/A
Country: N/A
Date: N/A 

I have lichen planus and cell marker HLA A-3 is associated with it. What exactly is HLA A-3?

HLA stands for Human Lymphocytic Antigen. It is one of the markers that would be checked for organ compatibility if you were ever an organ donor or recipient. The fact that its associated with lichen planus or is "linked", means only that the two traits sit close together on a chromosome. They do not necessarily have anything to do with each other.

One of your ancestors must have carried the lichen planus gene, and he/she also had the same type of HLA antigen that you carry. Since they are close together on a chromosome, they tend to travel together to the next generation. It is sort of like shuffling a deck of cards -- cards that were next to each other are more likely to end up next to each other than cards that started out far apart.

The fact that the HLA marker and l.p. are linked also means that if you have children, they could be tested to see if they're likely to also carry both.

Christine Ticknor, Ph.D.
Case Western Reserve University

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