Chromosome 13

Genes

Number of genes

Gene list

Diseases and disorders

• 13q deletion syndrome
• Bipolar disorder
• Bladder cancer
• Breast cancer
• Heterochromia
• Hirschsprung's disease
• Maturity onset diabetes of the young type 4
• Nonsyndromic deafness
• Propionic acidemia
• Retinoblastoma
• Schizophrenia
• Waardenburg syndrome
• Wilson's disease
• Patau syndrome
• Chronic Lymphocytic Leukemia
• Young–Madders syndrome

  Chromosomal conditions

• Retinoblastoma: A small percentage of retinoblastoma cases are caused by deletions in the region of chromosome 13 containing the RB1 gene. Children with these chromosomal deletions may also have intellectual disability, slow growth, and characteristic facial features. Researchers have not determined which other genes are located in the deleted region, but a loss of several genes is likely responsible for these developmental problems.
• Trisomy 13: Trisomy 13 occurs when each cell in the body has three copies of chromosome 13 instead of the usual two copies. Trisomy 13 can also result from an extra copy of chromosome 13 in only some of the body's cells. In a small percentage of cases, trisomy 13 is caused by a rearrangement of chromosomal material between chromosome 13 and another chromosome. As a result, a person has the two usual copies of chromosome 13, plus extra material from chromosome 13 attached to another chromosome. These cases are called translocation trisomy 13. Extra material from chromosome 13 disrupts the course of normal development, causing the characteristic signs and symptoms of trisomy 13. Researchers are not yet certain how this extra genetic material leads to the features of the disorder, which include severely abnormal cerebral functions, a small cranium, retardation, non functional eyes and heart defects.
• Other chromosomal conditions: Partial monosomy 13q is a rare chromosomal disorder that results when a piece of the long arm of chromosome 13 is missing. Infants born with partial monosomy 13q may exhibit low birth weight, malformations of the head and face, skeletal abnormalities, and other physical abnormalities. Intellectual disability is characteristic of this condition. The mortality rate during infancy is high among individuals born with this disorder. Almost all cases of partial monosomy 13q occur randomly for no apparent reason.

  Cytogenetic band