HLA-B27

[Grace66]

My father suffered from Ankylosing Spondalitis.  My sister's son also has AS.  I have not got the gene HLA-B27. Does that mean that my children cannot inherit the gene?  Also, can it skip a generation?  This might be a silly question but it worries me that my grandsons might be at risk.  

[Grace66]

Thank you for your reply.  I understand the multifactorial thing, as my Father's lifestyle and environment had a big bearing on his condition.

I still do not understand what you mean by 'the father's genetic status'.  Do you mean that the father needs to have a blood test for HLA-B27?  Do both parents have to have it before their children are likely to inherit it?  So if neither my husband nor I have HLA-B27
then our children cannot inherit it?  And that is as far as the gene can go in my family?

Thank you
Grace.

[Jordanna Joaquina, MS, CGC]

Ankylosing spondylitis is most likely a multifactorial condition, which means that it involves a combination of genetic, lifestyle and environmental factors.

Having one copy of the HLA-B27 variant (of the HLA-B gene) causes an increased risk to develop ankylosing spondylitis; however, most people with this variant do not develop any symptoms of ankylosing spondylitis even when inherited from an affected parent.

We all have two copies of the HLA-B gene -  we inherit one copy from each parent. As such, the chance for your children to have inherited the HLA-B27 variant is based not only on your genetic status but their father's genetic status as well.

[Maryham]

A related discussion, Tested Positive for HLA-B27 was started.

[gl248]

A related discussion, HLAB 27 Inheriting was started.

[Jordanna Joaquina, MS, CGC]

Having one copy of the HLA-B27 variant is sufficient to increase the risk of developing ankylosing spondylitis. However, we all have two copies of the HLA-B gene, one from our mother and the other from our father. As such, both parents (mom and dad) would need to be negative for the HLA-B27 variant in order for their children to have no chance of inheriting it. If one parent, mom or dad, has the variant, each child they have has a 50% chance of inheriting the variant.

Your grandchildren's risk would be based on your children's HLA-B27 "genetic status" (if they have the variant or not) as well as their spouse's.

You may benefit from meeting with a genetic counselor, who can review your family history and test results as well as discuss the benefits and limitations of HLA-B27 testing for your husband. You can find a genetic counselor in your area at the National Society of Genetic Counselors website or through companies like mine, AccessDNA.

Hope this helps clarify my answer!