Chromosome

CHROMOSOME 1

* Chromosome 1 is the largest human chromosome, spanning about 247 million base pairs (the building blocks of DNA) and representing approximately 8 percent of the total DNA in cells.

* This list of disorders associated with genes on chromosome 1

a.) Adenosine monophosphate (AMP) deaminase deficiency is a condition that can affect the muscles used for movement (skeletal muscles). People with this condition do not make enough of an enzyme called AMP deaminase. In most people, AMP deaminase deficiency does not cause any symptoms. People who do experience symptoms typically have muscle pain (myalgia) or weakness after exercise or prolonged physical activity. They often get tired more quickly and stay tired longer than would normally be expected. Some affected individuals have more severe symptoms, but it is unclear whether these symptoms are due solely to a lack of AMP deaminase or additional factors. Muscle weakness is typically apparent beginning in childhood or early adulthood.

b.) 1q21.1 deletion syndrome or 1q21.1 (recurrent) microdeletion is a rare aberration of chromosome 1.In a common situation a human cell has one pair of identical chromosomes on chromosome 1. With the 1q21.1 deletion syndrome one chromosome of the pair is not complete, due to the fact that a part of the sequence of the chromosome is missing.

The main symptoms are mental retardation and various physical anomalies. The manifestations in individuals are quite variable. Some people who have the syndrome can function in a normal way.

In 1q21.1, the '1' stands for chromosome 1, the 'q' stands for the long arm of the chromosome and '21.1' stands for the part of the long arm in which the deletion is situated. Next to the deletion syndrome, there is also a 1q21.1 duplication syndrome. While there is a part of the DNA missing with the deletion syndrome on a particular spot, there are two or three copies of a similar part of the DNA on the same spot with the duplication...