Answer
Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- The marriage that is likely to cause illness or disease should not be contracted so that it would not be a means of spreading illnesses.
2- However, it is the spouses’ own decision to complete the marriage contract with a different genotype or not as long as there is transparency about the health state of both spouses.
3- You should consult your doctor and, based on the information that he will provide, make your personal decision.
Answering your question, Sheikh Kifah Mustapha, the Imam and Director of The Prayer Center of Orland Park and representative for Dar El Fatwa of Lebanon in the US, states:
Separation between Spouses because of Defects
Most scholars approve separation between spouses because of defects. (Check the Book of Al-Muhalla 1899 Vol: 10 page: 72)
Imam Ibn Al-Qayyim approved separation, because the marriage contract was to be based on purity from defects. (Book of Zad Al-Ma`ad, Vol: 4, page: 30)
Type of Health Defects That Affect Marriage
The main health defects among scholars that are approved for separation are sexual ones that prevent the theme behind marriage like inability for intercourse or inability to have children, etc. Also added to these are mental problems. Leprosy, madness, impotence are few diseases to mention of both examples. (Al-Hidayah, page 307)
Now illnesses that are genetically inherited but do not prevent the right of spouses to enjoy the relationship between each other should be based on medical advice (percentage of inheriting diseases) and personal choices.
This means that fear of having children with such disease might not be of a concern because of medications and advanced medical research. Or it could be that husband agrees with wife not to have children from her but from another women.
Having said this, I suggest that you should consult your doctor and, based on the information that he will provide, make your personal decision.
Almighty Allah knows best.
Editor’s note: This fatwa is from Ask the Scholar’s archive and was originally published at an earlier date.