skip banner - Return to original view
site viewing options
 
Parents|Medical Information|Professionals|In your area|Campaigns

Chromosome Disorders

Chromosome abnormalities

Chromosome abnormalities have, by tradition, been defined as those abnormalities large enough to be seen down a light microscope. With more recent and sophisticated analytical techniques, much smaller abnormalities that cause symptoms can now be detected. Chromosome abnormalities often involve many different genes and they can be classified into two main types, numerical abnormalities and structural abnormalities. If these arise during formation of an egg or sperm cell, then the abnormality would be passed on to every cell in the child's body. If the abnormality arises in one of the new cells produced soon after an egg has been fertilised by a sperm, then only a proportion of the child's cells will be affected and this is called mosaicism. When a person carries such an abnormality, they are at risk of displaying the symptoms of the associated chromosome disorder.

View Background Background  |  Numerical abnormalities View Numerical abnormalities

Medical text written October 2001 by Dr B Searle. Approved October 2001 by Professor M A Hultèn. Additional material on small Supernumerary Marker Chromosomes written July 2005 by Dr T Liehr, Institute of Human Genetics and Anthropology, Jena, Germany. Last updated October 2006 by Dr B Searle, Unique - the Rare Chromosome Support Group. Approved October 2006 by Professor M A Hultèn, University of Warwick, Coventry, UK.

 

Tell us what you think of this information...

Print whole article Print whole article

 

This Web Site © Copyright, Contact a Family 2008
Contact a Family, 209-211 City Road, London EC1V 1JN
Tel: (020) 7608 8700

Registered Charity No. 284912. Charity registered in Scotland No. SC039169
Company limited by guarantee, registered in England and Wales No. 1633333.
HM Revenue & Customs charity tax reference No. XN54769. VAT Reg. No. GB 749 3846 82