Chromosome 18 (human)

Chromosome 18 (human)
Pair of human chromosome 18 (after G-banding). One is from mother, one is from father.
Chromosome 18 pair in human male karyogram.
Features
Length (bp)	80,373,285
Number of genes	657
Type	Autosome
Centromere position	Submetacentric
Identifiers
RefSeq	NC_000018
GenBank	CM000680

Ideogram of human chromosome 18. Mbp means mega base pair. See locus for other notation.

Chromosome 18 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 18 spans about 80 million base pairs (the building material of DNA) and represents about 2.5 percent of the total DNA in cells.

Identifying genes on each chromosome is an active area of genetic research. Because researchers use different approaches to predict the number of genes on each chromosome, the estimated number of genes varies. Chromosome 18 likely contains between 300 and 400 genes.

Genes

The following are some of the genes located in chromosome 18:

• DCC: Deleted in Colorectal Cancer
• FECH: ferrochelatase (protoporphyria)
• NPC1: Niemann-Pick disease, type C1
• SMAD4: SMAD, mothers against DPP homolog 4 (Drosophila)
• KC6: Keratoconus gene 6, discovery reported in 2005;

Diseases and disorders

The following diseases are some of those related to genes on chromosome 18:

• Erythropoietic protoporphyria
• Hereditary hemorrhagic telangiectasia
• Niemann-Pick disease Type C
• Porphyria
• Selective Mutism
• Edwards syndrome (Trisomy 18)
• Tetrasomy 18p
• Monosomy 18p
• Pitt Hopkins Syndrome 18q21

External links

• Chromosome18.org
• Chromosome18 Registry And Research Society in Europe.