Body odour of monozygotic human twins: a common pattern of odorant carboxylic acids released by a bacterial aminoacylase from axilla secretions contributing to an inherited body odour type

Abstract

It is currently not fully established whether human individuals have a genetically determined, individual-specific body odour. Volatile carboxylic acids are a key class of known human body odorants. They are released from glutamine conjugates secreted in axillary skin by a specific N a -acyl-glutamine-aminoacylase present in skin bacteria. Here, we report a quantitative investigation of these odorant acids in 12 pairs of monozygotic twins. Axilla secretions were sampled twice and treated with the N a -acyl-glutamine-aminoacylase. The released acids were analysed as their methyl esters with comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry detection. The pattern of the analytes was compared with distance analysis. The distance was lowest between samples of the right and the left axilla taken on the same day from the same individual. It was clearly greater if the same subject was sampled on different days, but this intra-individual distance between samples was only slightly lower than the distance between samples taken from two monozygotic twins. A much greater distance was observed when comparing unrelated individuals. By applying cluster and principal component analyses, a clear clustering of samples taken from one pair of monozygotic twins was also confirmed. In conclusion, the specific pattern of precursors for volatile carboxylic acids is subject to a day-to-day variation, but there is a strong genetic contribution. Therefore, humans have a genetically determined body odour type that is at least partly composed of these odorant acids.

Kin recognition inDrosophila: the importance of ecology and gut microbiota

“…Recent studies highlight the importance of gut microbiota on the evolution of mate preferences (Markov et al, 2009;Sharon et al, 2010), whereas others demonstrate that social behaviours can themselves alter gut microbiota communities (Koch and Schmid-Hempel, 2011). In the 1970s it was also hypothesised that gut microbiota could alter the scent of mammals (Gorman et al, 1974;Gorman, 1976;Singh et al, 1990;Kuhn and Natsch, 2009;Archie and Theis, 2011) and could thus have a key role in kin recognition. Examination of this hypothesis has continued to focus on mammals; however, gut microbiota is likely to also be important in social insects and potentially also in all insects whose communication relies on olfaction (Lizé et al, 2013).…”

Effective axillary malodour reduction by polyquaternium‐16‐containing deodorants

“…Between individuals, a high diversity of the axillary microbiome is common. A slight variability is even detectable between the right and left axilla of one person [17].…”

Analysis of pattern recognition and dimensionality reduction techniques for odor biometrics

“…The relation among the chemicals compounds that produce this scent remains constant over time even with changes in the diet or other transitory factors. Some studies [9,31] suggest that this primary odor depends on genetic factors thus, these compounds allow people identification. Furthermore, this genetic propensity by every individual to produce specific compounds has been reported even in studies with monozygotic twins [31], in which high correlations between the compounds of both siblings are found.…”

“…Some studies [9,31] suggest that this primary odor depends on genetic factors thus, these compounds allow people identification. Furthermore, this genetic propensity by every individual to produce specific compounds has been reported even in studies with monozygotic twins [31], in which high correlations between the compounds of both siblings are found. The compounds belonging Knowledge-Based Systems to secondary odor are also stable over time but are produced by a specific diet or other internal factors.…”