Chromosome 22

Genes

Number of genes

Gene list

Diseases and disorders

• Amyotrophic lateral sclerosis
• Breast cancer
• Cat eye syndrome
• Chronic myeloid leukemia
• DiGeorge syndrome
• Desmoplastic small round cell tumor
• 22q11.2 distal deletion syndrome
• 22q13 deletion syndrome or Phelan-McDermid syndrome
• Emanuel syndrome
• Ewing sarcoma
• Focal Segmental Glomerulosclerosis
• Li-Fraumeni syndrome
• TANGO2 deficiency
• Metachromatic leukodystrophy
• Methemoglobinemia
• Neurofibromatosis type 2
• Opitz G/BBB syndrome
• Renal medullary carcinoma
• Rubinstein-Taybi syndrome
• Waardenburg syndrome
• Schizophrenia

  Chromosomal conditions

• 22q11.2 deletion syndrome: Most people with 22q11.2 deletion syndrome are missing about 3 million base pairs on one copy of chromosome 22 in each cell. The deletion occurs near the middle of the chromosome at a location designated as q11.2. This region contains about 30 genes, but many of these genes have not been well characterized. A small percentage of affected individuals have shorter deletions in the same region.

• 22q11.2 distal deletion syndrome
• 22q13 deletion syndrome
• Other chromosomal conditions: Other changes in the number or structure of chromosome 22 can have a variety of effects, including intellectual disability, delayed development, physical abnormalities, and other medical problems. These changes include an extra piece of chromosome 22 in each cell, a missing segment of the chromosome in each cell, and a circular structure called ring chromosome 22 that is caused by the breakage and reattachment of both ends of the chromosome.
• Cat-eye syndrome is a rare disorder most often caused by a chromosomal change called an inverted duplicated 22. A small extra chromosome is made up of genetic material from chromosome 22 that has been abnormally duplicated. The extra genetic material causes the characteristic signs and symptoms of cat-eye syndrome, including an eye abnormality called ocular iris coloboma, small skin tags or pits in front of the ear, heart defects, kidney problems, and, in some cases, delayed development.
• A rearrangement of genetic material between chromosomes 9 and 22 is associated with several types of blood cancer. This chromosomal abnormality, which is commonly called the Philadelphia chromosome, is found only in cancer cells. The Philadelphia chromosome has been identified in most cases of a slowly progressing form of blood cancer called chronic myeloid leukemia, or CML. It also has been found in some cases of more rapidly progressing blood cancers. The presence of the Philadelphia chromosome can help predict how the cancer will progress and provides a target for molecular therapies.
• Emanuel syndrome is a translocation of chromosomes 11 and 22. Originally known as supernumerary der syndrome, it occurs when an individual has an extra chromosome composed of pieces of the 11th and 22nd chromosomes.

  Cytogenetic band