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What Complications Can Arise By Marrying Blood Relatives?
Question: Hello,
I have a very important question that I would love you answer in an objective manner, with all biases set aside.
This is of paramount importance in my life right now, and I want an answer purely based on science, not anything else.
My parents are cousins, my fathers father, and my mothers father are brothers.
Lets say, theoretically, that I marry my cousin (my father's sister's daughter) what kind of health-risks are there if we have children?
And please, I want to emphasize, I want a scientific response, and I heard about your website and that you've got doctors of high caliber
and therefore I am interested in your response.
Regards,
I have a very important question that I would love you answer in an objective manner, with all biases set aside.
This is of paramount importance in my life right now, and I want an answer purely based on science, not anything else.
My parents are cousins, my fathers father, and my mothers father are brothers.
Lets say, theoretically, that I marry my cousin (my father's sister's daughter) what kind of health-risks are there if we have children?
And please, I want to emphasize, I want a scientific response, and I heard about your website and that you've got doctors of high caliber
and therefore I am interested in your response.
Regards,
Brief Answer:
following risk may be there
Detailed Answer:
Thanks for the query.
The offspring of consanguineous unions may be at increased risk for recessive disorders because of the expression of autosomal recessive gene mutations inherited from a common ancestor.
The closer the biological relationship between parents, the greater is the probability that their offspring will inherit identical copies of one or more detrimental recessive genes. For example, first cousins are predicted to share 12.5% (1/8) of their genes. Thus, on average, their progeny will be homozygous at 6.25% (1/16) of gene loci (Bennett et al. 2002).
In general, consanguinity does not increase the risk for autosomal dominant conditions in offspring when one of the parents is affected.
Hope i helped you.
following risk may be there
Detailed Answer:
Thanks for the query.
The offspring of consanguineous unions may be at increased risk for recessive disorders because of the expression of autosomal recessive gene mutations inherited from a common ancestor.
The closer the biological relationship between parents, the greater is the probability that their offspring will inherit identical copies of one or more detrimental recessive genes. For example, first cousins are predicted to share 12.5% (1/8) of their genes. Thus, on average, their progeny will be homozygous at 6.25% (1/16) of gene loci (Bennett et al. 2002).
In general, consanguinity does not increase the risk for autosomal dominant conditions in offspring when one of the parents is affected.
Hope i helped you.
Above answer was peer-reviewed by :
Dr. Vinay Bhardwaj
Hello Doctor,
Thanks alot for the answer.
If I understand your answer correctly, there may be a health-issue to our offspring if my + her parents already have healthproblems because the risk that our offspring inherits the recessive genes increases?
You mentioned: "on average, their progeny will be homozygous at 6.25% (1/16) of gene loci" - That is for first cousins.
But what if, like in my case, my parents are already cousins (their fathers are brothers), and I want to marry my cousin cousin again (the daughter of my fathers sister) will there be a greater risk of health issue for our offspring? If yes, how much greater?
Thanks,
Thanks alot for the answer.
If I understand your answer correctly, there may be a health-issue to our offspring if my + her parents already have healthproblems because the risk that our offspring inherits the recessive genes increases?
You mentioned: "on average, their progeny will be homozygous at 6.25% (1/16) of gene loci" - That is for first cousins.
But what if, like in my case, my parents are already cousins (their fathers are brothers), and I want to marry my cousin cousin again (the daughter of my fathers sister) will there be a greater risk of health issue for our offspring? If yes, how much greater?
Thanks,
Brief Answer:
genetic counselling may help.
Detailed Answer:
Thanks for the query.
Yes it may increase the risk of transmission of the disease.
I am not sure about how much risk increases!, you need to consult genetic specialist for more details.
To avoid health sisk in offspring, Comprehensive genetic education and premarital genetic counselling programs can help.
Hope i helped you.
genetic counselling may help.
Detailed Answer:
Thanks for the query.
Yes it may increase the risk of transmission of the disease.
I am not sure about how much risk increases!, you need to consult genetic specialist for more details.
To avoid health sisk in offspring, Comprehensive genetic education and premarital genetic counselling programs can help.
Hope i helped you.
Above answer was peer-reviewed by :
Dr. Vinay Bhardwaj
Thanks for your answer.
Ok, I understand.
Do you have any info on the general case? For instance, you mentioned that the general case average risk is 6.25% inheritance of recessive genes if the offspring is between first cousins".
How can one go about to calculate if the case is like mine? I.e, my parents are already cousins and I want to marry my cousin? Again, I just want the general case, or if there is any calculation for it like the calculation for the first-cousin case.
Righ now I am basically probing information, afterwhich I'll seek geneic consultation. But I would love if you could give me a perspective on the general case.
Ok, I understand.
Do you have any info on the general case? For instance, you mentioned that the general case average risk is 6.25% inheritance of recessive genes if the offspring is between first cousins".
How can one go about to calculate if the case is like mine? I.e, my parents are already cousins and I want to marry my cousin? Again, I just want the general case, or if there is any calculation for it like the calculation for the first-cousin case.
Righ now I am basically probing information, afterwhich I'll seek geneic consultation. But I would love if you could give me a perspective on the general case.
Brief Answer:
here is the solution
Detailed Answer:
Thanks for the follow up.
If your parents and you do not have any disease (which is linked to recessive transmission) then you need not to worry much.
There is no calculator (as per my knowledge) to predict the risk as in your case where your parents are also cousins.
General case is not different than your case. Average risk which i already mentioned relates to you also.
Hope i helped you.
here is the solution
Detailed Answer:
Thanks for the follow up.
If your parents and you do not have any disease (which is linked to recessive transmission) then you need not to worry much.
There is no calculator (as per my knowledge) to predict the risk as in your case where your parents are also cousins.
General case is not different than your case. Average risk which i already mentioned relates to you also.
Hope i helped you.
Note: For detailed guidance on genetic screening consult a genetics specialist
Above answer was peer-reviewed by :
Dr. Vinay Bhardwaj
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