A study of CYP2C19*2, *3 and *7 in different Sudanese ethnic groups and their response to omeprazole based triple therapy in Khartoum, Sudan 2016-2017

Abstract

Background: Peptic ulcer disease has a high burden worldwide and the commonest causative agent is H. pylori which are usually eradicated with omeprazole-based triple therapy. Pharmacogenetics is an important branch of pharmacology and should be applied to assist the clinical usage of medicines which has a strong relation with enzyme activity of certain genes and alleles known through the literature. CYP2C19 is known to affect the activity of omeprazole and this will result in different responses to treatment. The commonest alleles through the literature are CYP2C19*2, and CYP2C19*3 which vary according to different ethnicity of different populations. Aim: In Sudan, there are versatile ethnic groups which might affect the response to treatment by many drugs dependent genotypes for example CYP2C19 and Omeprazole interaction and hence studies in this area should be done as they are few. Methodology: A purposeful convenient sampling; in which patients with peptic ulcer disease and treated with omeprazole were reviewed and the PCR is used to differentiate the CYP2C19 different alleles in patients presenting from February 2016 to January 2017. Results: In the present study we investigated the distribution of three common gene variants affecting the omeprazole treatment of peptic ulcer disease and H. pylori eradication namely to CYP2C19*2, *3 and *7. The CYP2C19*2 mutation was found among all seven ethnic groups of Sudan, Arabs mostly 17 (139) followed by Darforians 9 (139), Beja 6 (139) and Nilotics 6 (139), Nuba 5 (139) then, Nubians 3 (139) and Fulani 1 (139), p=0.048 which is significant. Regarding CYP2C19*3 mutation of this allele is found in certain ethnic groups Arabs 6 (139), Nubians 6 (139) and Nuba 2 (139), p=0.043 significant. There is no mutation found among different Sudanese ethnic groups in CYP2C19*7. Arabs are normal homozygotes 6 (139) and Darforians 1 (139). Nuba 1 (139) were found to be heterozygotes in this allele p=0.038 significant. Treatment of H. pylori with omeprazole-based triple therapy was used in 110 (139) and no significant correlation found with the different ethnic groups of Sudan. Conclusion: These data indicate that Sudanese seven ethnic groups showed activity of CYP2C19*2, CYP2C19*3 were they took omeprazole based triple treatment and some of them showed activity to CYP2C19*7.

Ethnopsychopharmacology: Clinical and scientific writing pearls

“… 62 Again, intergroup differences should be recognized, but the generalized incidence of results for the CYP2C19 poor-metabolizer status varies across individuals of Asian (13% to 23%), African (6%), and European (2% to 5%) ancestries. 62 , 63 …”