Williams syndrome is caused by a person missing more than 25 genes from a specific area of chromosome 7 (a “deletion”). The loss of these genes contributes to the characteristic features.

How is deletion syndrome inherited?

When an affected child inherits a chromosomal deletion from a parent, it is inherited in an autosomal dominant pattern , which means one copy of the altered chromosome in each cell is sufficient to cause the disorder.

What does chromosome 7 indicate?

Abnormalities involving the inheritance of chromosome 7 can cause Russell-Silver syndrome, a rare condition characterized by slow growth, distinctive facial features, delayed development, speech and language problems, and learning disabilities.

What is a genetic deletion?

Deletion is a type of mutation involving the loss of genetic material. It can be small, involving a single missing DNA base pair, or large, involving a piece of a chromosome.

What are the causes of deletion syndrome?

2 deletion syndrome is caused by a deletion of a small part of chromosome 22 near the middle of the chromosome at a location known as q11. 2. In most cases, the syndrome occurs for the first time in the affected person; about 10% of cases are inherited from a parent. It is inherited in an autosomal dominant manner.

What causes 2q2 deletion syndrome?

2q23.1 deletion syndrome is caused by the loss of a small piece of DNA in one copy of chromosome 2, one of the 23 pairs of chromosomes in each cell in our bodies. Most cases of 2q23.1 deletion syndrome are de novo, which means the deletion was not passed down from either parent.

What is the pathophysiology of 2q37 syndrome?

2q37 deletion syndrome is caused by a deletion of genetic material from a specific region in the long (q) arm of chromosome 2. The deletion occurs near the end of the chromosome (terminal deletion) at a location designated 2q37.

What are the symptoms of microdeletion of chromosome 2q33?

Urquhart et al. (2009) reported a girl with a de novo heterozygous 4.5-Mb microdeletion of chromosome 2q33.1. She had cleft soft palate, feeding problems, febrile seizures, and delayed psychomotor development with poor speech.

What is microdeletion syndrome caused by?

2q23.1 microdeletion syndrome is caused by the loss of a small piece of one copy of chromosome 2, one of the 23 pairs of chromosomes in each cell in our body. Losing this small piece of chromosome 2 means that people with this microdeletion are missing one copy of the gene called MBD5.