The conclusion could open the door to treating the disorder with engineering a way to overcome its activity.
Hypersexual disorder is recognized as a compulsive sexual behaviour disorder, classified as an impulse control disorder by the World Health Organisation (WHO). It can be identified by obsessive feelings of sex, an addiction to perform sexual acts, a lack of control, or sexual habits that give potential problems or risks. While prevalence estimates vary, the literature indicates that hypersexual disorder affects 3-6% of the population.
Controversy encompasses diagnosis because it often occurs adjacent other mental health issues, suggesting it could be an expansion or manifestation of a current mental disorder.
The scientists assessed DNA methylation patterns in the blood of 60 patients by the hypersexual disorder and matched them to samples from 33 healthy volunteers.
They studied 8,852 regions of DNA methylation associated with nearby microRNAs to identify any differences between samples.
DNA methylation can alter gene expression and the function of genes, typically acting to decrease their activity.
Where changes in DNA methylation were detected, the researchers examined levels of gene expression of the associated microRNA.
MicroRNAs are expressly engaging as they can pass the blood-brain barrier and modulate or degrade the expression of up to several hundred several genes in brain and other tissues.
They also analysed their findings to samples from 107 subjects, 24 of whom were alcohol dependent, to search an association with addictive behaviour.
Results recognised two regions of DNA that were altered in hypersexual disorder patients.
The normal function of DNA methylation was disrupted and an associated microRNA, involved in gene silencing, was found to be under expressed.
The analysis showed that the microRNA identified, microRNA-4456 targets genes that are normally expressed at particularly high levels in the brain and that are included in the regulation of the hormone oxytocin. With gene silencing reduced, oxytocin may be assumed to be at elevated levels, although the current study does not confirm this.
It has been seen in specific vole and primate species the neuropeptide oxytocin plays a central role in the regulation of pair-bonding behaviour.
Previous studies have described that oxytocin is associated with the direction of social and pair-bonding, sexual reproduction and aggressive behaviour in both men including women.
The connection with alcohol-dependent subjects showed the same DNA region to be significantly under-methylated.
It’s suggesting that it may be originally associated with the addictive components of hypersexual disorder, such as sex addiction, dysregulated sexual desire, compulsivity and impulsivity.
The authors document a limitation of the study, that the mean variation in DNA methylation between hypersexual disorder subjects and healthy volunteers was only around 2.6%.
So the impact on physiological differences might be called into issue.
The main evidence outlines that just subtle methylation differences concerning complex conditions such as depression or schizophrenia.