Understanding Rare Chromosome and Gene Disorders


Rare chromosome disorders, copy number variants and single gene disorders include extra, missing or re-arranged chromosome or genetic material but do not include the more common chromosome conditions such as Down's Syndrome.

Keeping you informed

Rare chromosome disorders include extra, missing or re-arranged chromosome material but do not include the more common chromosome conditions such as Down’s Syndrome.  Unique also deals with rare autosomal dominant single gene disorders (only one copy of the mutated gene is necessary for the disorder to be present) but NOT autosomal recessive single gene disorders (in which two copies of the mutated gene, one from Mum and one from Dad, are needed for the disorder to be present). Using the latest technology, it is now possible for smaller and more complex chromosome and gene disorders to be identified. The amount of chromosome  or genetic material duplicated, missing or re-arranged can vary a great deal. This means that it might be difficult to identify two people who have exactly the same chromosome or gene disorder. The clinical problems of those affected can also vary enormously even when the chromosome or gene diagnoses are similar.

Individually rare chromosome  and gene disorders are indeed very rare but collectively they are common. In fact at least one in every 200 babies is born with a rare chromosome or gene disorder, many babies having symptoms from birth or early childhood. The rest might be affected when they grow up and try to have babies of their own – multiple miscarriages, fertility problems, stillbirths or the birth of a disabled child. Some of these chromosome and gene disorders are so rare that they are actually unique. It is usually immediately following diagnosis that affected families and individuals have the greatest need for emotional and practical support and above all, for information. But even among the more common “rare” disorders, it is likely that the professionals in the local community – the GP, Social Worker or even hospital specialists – will have never before come across anyone with the same disorders. The usual sources of support are not available to affected families, yet the effects of the disorders can be devastating. The vast majority of families have a desperate feeling of isolation. Under the umbrella of Unique membership, families can benefit from mutual support and linking even though the chromosome and gene disorders may be quite different.


Last edited by Beverly Searle BSc(Hons) PhD CBiol MRSB 5th January 2018

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