, a Cell Press publication. This GWAS, which included 6,175 ED cases, is the largest study till date. Moreover, in this study, the research team discovered a new locus linked to the pathogenesis of ED.
Erectile dysfunction (ED) is a condition in males that is characterized by the inability to develop or maintain a penile erection adequate for sexual intercourse. ED can be a sign of an underlying physical or psychological condition. It can result in stress, relationship problems and low self-esteem.
The prevalence of ED is age-dependent, with 20-40 percent men aged 60-69 years being most affected.
The genetic basis of ED remains poorly understood, primarily due to the lack of well-designed genetic association studies. This aspect has been addressed in the present study.
A large-scale genome-wide association study (GWAS) of ED was carried out in 6,175 cases among 223,805 European men. The research team used cutting-edge genetic analysis techniques, which enabled them to elucidate the complex correlations between diabetes and ED. They discovered a new locus at 6q16.3 of chromosome 6, between the MCHR2
(melanin-concentrating hormone receptor 2) and SIM1
(single-minded homolog 1) genes.
The study was conducted on data from the population-based UK Biobank (UKBB), the Estonian Genome Center of the University of Tartu (EGCUT) cohorts, and hospital-recruited Partners HealthCare Biobank (PHB) cohort.
The following are the major findings of the study:
- Genetic predisposition to type 2 diabetes is causally linked to the etiology of ED, which provides solid evidence that diabetes is a cause of ED
- Prevalence of ED in the cohorts was 1.53 percent in UKBB, 7.04 percent in EGCUT and 25.35 percent in PHB
- GWAS in the UKBB cohort revealed a single genome-wide significant locus at 6q16.3 of chromosome 6
- Pathogenesis of ED is caused by common non-coding variants on the SIM1 gene
- High systolic blood pressure (SBP) is linked to a higher risk of ED
- Genetic risk of coronary heart disease (CHD) exhibits weak effects on the risk of ED, which suggests that pathways leading to CHD may be implicated in ED
Dr. Anna Murray, BSc, PhD, who is an Associate Professor in Human Genetics at the University of Exeter Medical School (UEMS), is a co-senior author on the study. She said: "Erectile dysfunction affects at least one in five men over 60, yet up until now little has been known about its cause. Our paper echoes recent findings that the cause can be genetic, and it goes further. We found that a genetic predisposition to type 2 diabetes is linked to erectile dysfunction. That may mean that if people can reduce their risk of diabetes through healthier lifestyles, they may also avoid developing erectile dysfunction."
Dr. Michael Holmes, BSc (Hons), MBBS, MSc, PhD, MRCP, is an Associate Professor in the Nuffield Department of Population Health at the Medical Sciences Division, University of Oxford, and is one of the study's senior authors. He said: "Our finding is important as diabetes is preventable and indeed one can now achieve 'remission' from diabetes with weight loss, as illustrated in recent clinical trials. This goes beyond finding a genetic link to erectile dysfunction to a message that is of widespread relevance to the general public, especially considering the burgeoning prevalence of diabetes."
Dr. Jonas Bovijn, MBChB, MSc, DLSHTM, is a DPhil student in Genomic Medicine and Statistics at the Wellcome Centre for Human Genetics, University of Oxford, and is also the co-first author of the study. He said: "We know that there is observational evidence linking erectile dysfunction and type 2 diabetes, but until now there has not been definitive evidence to show that predisposition to type 2 diabetes causes erectile dysfunction."
The present study corroborated previous findings that ED has a genetic link. Moreover, the study further strengthens the fact that a specific region in the genome is linked to the pathogenesis of ED. The findings provide novel insights into the biological basis of ED. The findings suggest that by leading a healthier lifestyle, the risk of diabetes could be reduced, thereby preventing the occurrence of ED.
The paper also potentially paves the way for the development of new targeted molecular therapies for ED.
Further large-scale GWAS of ED will be carried out in order to provide additional clarity on its genetic basis, etiology, as well as shed light on potential new therapies. Reference :
- GWAS identifies novel risk locus for erectile dysfunction and implicates hypothalamic neurobiology and diabetes in etiology - (https://www.biorxiv.org/content/biorxiv/early/2018/03/15/283002.full.pdf)