Genetics Body odor

body odor largely influenced major histocompatibility complex (mhc) molecules. these genetically determined , play important role in immunity of organism. vomeronasal organ contains cells sensitive mhc molecules in genotype-specific way.

experiments on animals , volunteers have shown potential sexual partners tend perceived more attractive if mhc composition substantially different. married couples more different regarding mhc genes expected chance. behavior pattern promotes variability of immune system of individuals in population, making population more robust against new diseases. reason may prevent inbreeding.

the abcc11 gene known determine axillary body odor , type of earwax. loss of functional abcc11 gene caused 538g>a single-nucleotide polymorphism, resulting in loss of body odor in people homozygous it. firstly, affects apocrine sweat glands reducing secretion of odorous molecules , precursors. lack of abcc11 function results in decrease of odorant compounds 3m2h, hmha, , 3m3sh via reduced secretion of precursor amino-acid conjugates 3m2h–gln, hmha–gln, , cys–gly–(s) 3m3sh; , decrease of odoriferous steroids androstenone , androstenol, possibly due reduced levels , secretion of dheas , dhea (possibly bacterial substrates odoriferous steroids). secondly, associated reduced/atrophic size of apocrine sweat glands , decreased protein (such asob2) concentration in axillary sweat.

the non-functional abcc11 allele predominant among east asians (80–95%), low in other ancestral groups (0–3%). of world s population have gene codes wet-type earwax , normal body odor; however, east asians genetically predisposed allele associated dry-type earwax , reduction in body odor. east asians (chinese, koreans, , japanese) have fewer apocrine sweat glands compared people of other descent, making east asians less prone body odor. reduction in body odor , sweating may due adaptation colder climates ancient northeast asian ancestors.

research has indicated strong association between people axillary osmidrosis , abcc11-genotypes gg or ga @ snp site (rs17822931) in comparison genotype aa.

* nd indicates no detectable peak found on [m+h]+ ion trace of selected analyte @ correct retention time.

* hmha: 3-hydroxy-3-methyl-hexanoic acid; lc-ms: liquid chromatography-mass spectrometry; 3m2h: (e)-3-methyl-2-hexenoic acid; 3m3sh: 3-methyl-3-sulfanylhexan-1-ol.