Marrying close relatives

My boyfriend's mother's father's father and my mother's father's father are brothers. So, we are considered as a second cousins or third cousins???
If we get married, will there be any problem for our offspring???
Will there be any birth defects???
Any advice for us?
Thanks!

[Lisa Kessler, MS, CGC]

The relationship that you describe would make you and your boyfriend third cousins.  
Genetic counseling may help you to put your risks in context. Everyone has the risk of having children with problems, but because cousins share the same close ancestors, it is slightly more likely that they might share a disease gene.

Third cousins are predicted to share 0.78% (1/128) of their genes.  In contrast, first cousins are predicted to share 12.5 % (1/8) of their genes.   The closer the biological relationship is between parents, the greater proportion of genes shared, and the greater the chance to have a child with birth defects.  

The background risk that every couple faces of having children with birth defects is about 2-3%.  Genetic counseling will help define this for you personally based on your family history and ethnic background.

There are no special tests for cousin couples. The same tests a genetic counselor would discuss with any couple thinking about having children based on family history and ethnicity is what you should expect.

You can find a genetic counselor in your area through the National Society of Genetic Counselors or through companies like mine, DNA Direct.

[cousin527]

my first marriage was unsuccessfull because i did not have full known of her so we broke up.
now i want to get married with my first cousin who love each other.
my question is that what is the risk of have  defect childern from this relationship and second how high is the risk??

[jbug217]

A related discussion, birth defects between cousins was started.

[zee335]

A related discussion, Marriage to relatives was started.