Consanguinity and Genetic Diseases in Egypt
Samia A. Temtamy
Table of Contents
References
In Egypt, both consanguinity and genetic diseases have been known since the
Pharaos. Islamic and current Egyptian laws prohibit marriages closer than first
cousins.
Figure 1. Egypt
Egypt, a Mediterranean North African country with a central location at the junction of
3 continents attracted gene flow from various invaders. Geneticists classify unions
between second cousins or closer as consanguineous. Children of first-cousin
marriages inherit identical gene copies from each parent at 1/16 of their gene loci
(F=0.0625).
Birth incidence of malformations in Egyptian newborns ranges between 1.16 and
3.17%. The frequency of malformations at birth showed that CNS malformations were
the most common (9.33/1000). Studies of parental consanguinity in the Egyptian
population showed a frequency ranging from 20 to 42%. Parental consanguinity rates
in groups of Egyptian patients with various birth defects were high suggesting a high
rate of autosomal recessive disorders related to other patterns of inheritance.
Parental consanguinity rates in Egyptian patients with specific malformations and
genetic diseases affecting various systems and organs were extensively reviewed.
High rates of consanguinity were found in autosomal recessive and polygenic
disorders. There was no increase in autosomal dominant, X linked or chromosomal
disorders.
New autosomal recessive disorders were first defined among Egyptians. A
phenomenon of multiple genetic disorders in the same individual or sibship was
observed. Also, because of high parental consanguinity quasidominant pattern of
inheritance was observed.
The high consanguinity rate reported in our society results in an increased rate of
certain genetic diseases, mainly autosomal recessive and polygenic disorders.
A program for public education and teaching of medical schools is needed to alert the
public.
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