XYY syndrome, also known as 47,XXY syndrome affects males and is defined by an extra copy of the Y-chromosome. This syndrome is usually a result of random nondisjunction during meiosis II of spermatogenesis which results in sperm cells with an additional Y-chromosome. Most of the cases of this syndrome therefore are not inherited. Children with this syndrome appear normal with no medical problems or illnesses.Their intellectual ability is considered to be normal even though they have a need for learning support. They also are very vulnerable to stress along with behaviour problems.
- ↑ Genetics Home Reference. (2014). 47,XYY Syndrome. Available: http://ghr.nlm.nih.gov/condition/47xyy-syndrome. Last accessed 25th Nov 2014.
- ↑ National Genetics and Genomics Education Centre (NHS). (2013). 47, XYY. Available: http://www.geneticseducation.nhs.uk/genetic-conditions-54/632-47-xyy-new. Last accessed 26th Nov 2014.
- ↑ Rare Chromosome Disorder Support Group. (2005). Unique XYY. Available: http://www.rarechromo.org/information/Chromosome_Y/XYY%20FTNW.pdf. Last accessed 26th Nov 2014.