Evolutionary interplay of single nucleotide polymorphisms at the promoter region of TNF-α gene in different clinical outcomes of malaria in India.
Infect Genet Evol
; 69: 107-116, 2019 04.
Article
in En
| MEDLINE
| ID: mdl-30677532
ABSTRACT
Host genetic factors are frequently ascribed to differential malaria outcomes as a by-product of evolutionary adaptation. To this respect, Tumor Necrosis factor alpha (TNF-α), a human cytokine, is known to be associated with malaria through its differential regulation in diverse malaria manifestations. Since diversity in differential malaria outcome is uncommon in every endemic settings, possible association of TNF-α and malaria is not commonly established. In order to check for association between the occurrence of Single Nucleotide Polymorphisms (SNPs) in the TNF-α gene with different malaria manifestations, we have sequenced a 4011â¯bp region constituting the promoter and the whole gene of human TNF-α in 61 patients [(16 cerebral plus severe (SCM), 21 severe (SM) and 24 uncomplicated (UM)] samples in a highly malaria endemic state (Odisha) of India. Multiple sequence alignment revealed presence of six SNPs (-1031â¯Tâ¯>â¯C, -863Câ¯>â¯A, -857Câ¯>â¯T, -308Gâ¯>â¯A, -806Câ¯>â¯T, +787Câ¯>â¯A), out of which the -806Câ¯>â¯T and +787Câ¯>â¯A are novel in malaria patients in general and the +787Câ¯>â¯A was detected for the first time in humans. Although alleles due to six different SNPs segregate differentially in the three groups of malaria (SCM, SM and UM) in the present study, interestingly, for the -1031â¯Tâ¯>â¯C position, the frequency of individuals possessing the homozygous rare allele was higher in the SCM group with a higher number of heterozygotes in the UM group. The Tajima's D values considering all the SNPs in a defined group were positive and statistically insignificant conforming no evolutionary constraint. However, statistically significant deviation from expectation under Hardy-Weinberg equilibrium for -1031â¯Tâ¯>â¯C SNP in the UM group points towards the probable role of natural selection providing some kind of protection to malaria in Odisha, India.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Promoter Regions, Genetic
/
Tumor Necrosis Factor-alpha
/
Evolution, Molecular
/
Genetic Predisposition to Disease
/
Polymorphism, Single Nucleotide
/
Malaria
Limits:
Female
/
Humans
/
Male
Country/Region as subject:
Asia
Language:
En
Journal:
Infect Genet Evol
Journal subject:
BIOLOGIA
/
DOENCAS TRANSMISSIVEIS
/
GENETICA
Year:
2019
Document type:
Article
Affiliation country:
India