Episode 42: Section 10th: Genetic Impact of Marriage between Relatives (2/4)


On the other hand, Dr. `Umar Al Alfi stated two principles of genetics.

First: As the source of heredities by marriage becomes far the offspring comes stronger. This rule was extracted from the results shown by the experiments on mating between animals, as well as from the experiments on plant pollination.

Second: If father and mother both carry the same flawed gene it will allow the hereditary disease to appear in the offspring. And the possibility of this phenomenon would be one of four on each occasion, while the possibility of carrying defective gene by both, father and mother will rise to the same extent as the kinship between them will be nearer."

In addition, Dr. `Umar Al Alfi says: that in multiple studies that were conducted before in Kuwait - showed that miscarriages were higher in consanguineous marriages by 9.89% than in distant marriages by 7.46%.

The average birth weight in consanguineous marriages was (3274 g) that is less than the average weight in distant marriages (3326 g).

The incidence of some hereditary diseases in the marriages of relatives is higher than in marriages into distant. –Through scientific point of view -The most important of these diseases is the mental retardation called (Down’s syndrome). There were 14 cases of disease between the 3989 consanguineous marriages – i.e. the ratio of 3.5 cases per thousand, in comparison to 6 cases in the 7436 marriages between distant - i.e. the ratio of 0.8 per thousand.

The new point in this research is that the disease (Down’s syndrome) is resulted from an imbalance in the division of chromosomes, and the scientific conclusion here is that this case is affected by a recessive gene that increases in consanguineous marriages (1). End of quote.

Al Hafiz Yusuf Musa quoted Al Ahram newspaper that Dr. Fouad Ash-Sherbini (2) has conducted a study that concluded that inbreeding causes disorders in immune systems and allergies and weakens the resistance of children to microbes. The most important diseases are (Mediterranean Anemia), a kind of lack of hemoglobin (Anemia), Diabetes, Gout, and chemical disorders and visual impairment. These diseases appear in the second generation directly. The average of hereditary vision impairment rose to 50% of the total cases of low vision. Such children are genetically ready to the risk of heart disease, Asthma, Epilepsy, Deafness, though it is not a condition that one of the parents is quietly suffering from the disease, but merely their kinship is enough for the child to acquire what the ancestors had.

The studies carried out by the Higher Institute of Health suggest that the incidence of Pre-eclampsia and death among infants and toddlers is higher in consanguineous marriages when compared to marriages of non-relatives (3). End of quote.



(1) Research Paper on (Marry a stranger, you will don't have a weak child), as was mentioned above, when we presented the opinions of scholars on this narration.

(2) Former head of the Department of Children's Care and Maternity at the High Institute of Public Health, Egypt.

(3) Sex between Islam and the secularism (321), where the author said: These studies were conducted in Egypt, quoting Al-Ahram newspaper, Issue number (36 451) 26/9/1986.

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