A to Z of syndromes

A-Z syndromes: Klinefelter syndrome

How to recognise and support children who have this rare neurological condition

Klinefelter syndrome, affecting males, is a collection of characteristics that occurs as a result of two or more X chromosomes. The syndrome was named after Harry Klinefelter, an American endocrinologist, and is common – occurring in all races. It is thought that one male in every 500 live births is affected and the incidence is rising. However, this may be due to increasing awareness, reflective of the sophistication of the methods to diagnose.

Although a chromosomal abnormality it is not inherited and usually occurs as a random mutation, with advancing maternal age being thought to increase the risk slightly. This condition is a result of non-disjunction during meiosis, this is when the sex chromosomes fail to separate in the ovum or the sperm. The ovum, once fertilised, carries additional X sex chromosomes, as well as the father’s Y sex chromosome which codes for a


Want to read more?

Unlock full access to RCNi Plus today

Save over 50% on your first three months:

  • Customisable clinical dashboard featuring 200+ topics
  • Unlimited online access to all 10 RCNi Journals including Nursing Children and Young People
  • RCNi Learning featuring 180+ RCN accredited learning modules
  • NMC-compliant RCNi Portfolio to build evidence for revalidation
  • Personalised newsletters tailored to your interests

This article is not available as part of an institutional subscription. Why is this?