well that will not change anytime soon. It’s not about marrying cousins only. Qataris don’t marry outside their own tribe . Marrying Qataris of Persians & Africans roots is still Considered a big taboo among Arab tribes Qataris.

To make the matter worst, Even some Arab tribes don’t marry from each other or from the Bedouins (Although Bedouins are also considered Arab tribes).

It’s not only about birth defects you know. Also non-communicable diseases ( Blood sugar, Obesity, etc) .