Maghrebian mutations

Question

Hello,
Is it true that the mutations of persons of Maghrebian and sub-Saharian origin lead to lighter forms of cystic fibrosis?
Thanks in advance.
Cordially.

Answer

Hello,

It is difficult to answer precisely your question. The frequency of mutations known to cause cystic fibrosis and identified as statistically associated with either classical or moderate forms varies according to population. The nearly 2,000 currently known mutations in the cystic fibrosis gene have been identified mainly in Western countries with a high percentage of population of European origin. The frequency of different mutations is very poorly known for populations living outside Europe or America (especially North America). The functional impact of the specific mutations of these populations ("severe" mutation or "moderate" mutation) is also poorly understood.

An article published in November 2016 reports the results of a study conducted in close to 800 patients of African origin living in 6 countries of America and diagnosed with confirmed cystic fibrosis. Only half of the 1600 mutations (2 per patient) carried by these patients could be identified whereas it is in more than 90% of patients of European origin.

I remind you that the relationship between the mutations (genotype) and the evolutionary form of the disease (phenotype) has only statistical value. The genotype does not predict in a given individual the evolutionary form of the disease that depends on many other environmental and genetic factors.

Hoping to have answered your question.
Best regards,
Gilles RAULT, CRCM of Roscoff

24.02.2017