During adolescence, on average 33 percent of males are estimated to exhibit signs of gynecomastia. Gynecomastia in older men is estimated to be present in 24–65 percent of men between the ages of 50 and 80. Estimates on asymptomatic gynecomastia is about up to 70% in men aged 50 to 69 years.The prevalence of gynecomastia in men may have increased in recent years, but the epidemiology of the disorder is not fully understood. The use of anabolic steroids and exposure to chemicals that mimic estrogen in cosmetic products, organochlorine pesticides, and industrial chemicals have been suggested as possible factors driving this increase. According to the American Society of Plastic Surgeons, breast reduction surgeries to correct gynecomastia are fairly common but has been a recent decline. In 2020, there were over 18,000 procedures of this type performed in the United States which is down 11% compared to in 2019. Society and culture
Gynecomastia can result in psychological distress for those with the condition. Support groups exist to help improve the self-esteem of affected people.In 2019, a 12-person Philadelphia jury awarded $8 billion in punitive damages to plaintiffs tied to the use of risperidone. Risperidone is an atypical antipsychotic that was originally approved to treat psychosis, but its use in children, including those with autism, ADHD, and schizophrenia diagnoses, has grown over the last two decades.In Murray v. Janssen Pharmaceuticals, Murray was a Risperidone user who was prescribed the medication at age nine and developed male breasts.
The diaphragmatic hernia found in the 8p23.1 deletion syndrome has not been found in the 8p23.1 duplication syndrome to date. The duplication may be associated with copy number changes of the adjacent olfactory receptor/defensin repeats (ORDRs) that predispose to the 8p23.1 deletion and duplication syndromes. High total copy numbers of these repeats have been associated with predisposition to psoriasis and low copy number with predisposition to Crohns disease. Genetics
The duplication includes ~3.75 Mb between the distal and proximal ORDRs at either end of band 8p23.1. The copy number of the adjacent repeats may also be altered. The 8p23.1 duplication syndrome cannot be distinguished using conventional cytogenetics from high level copy number variation of the repeats themselves.Both de novo cases and families with transmitted duplications from parents of both sex are known. The duplication is believed to arise de novo as a result of non-allelic homologous recombination (NAHR) between the proximal and distal ORDRs. NAHR is also thought to give rise to the reciprocal microdeletion syndrome, the polymorphic inversion between the ORDRs and a variety of other large scale abnormalities involving the short arm of chromosome 8. Diagnosis
Phenotypes
See also
Chromosome 8 (human)

References
External links

DECIPHER database description