Small Integral Membrane Protein 20 (SMIM20)

Chromosome 4 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 4 spans more than 186 million base pairs and represents between 6 and 6.5 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.Changes in chromosome 4 have been identified in several types of human cancer.These genetic changes are somatic, which means they are acquired during a person's lifetime and are present only in certain cells. For example, rearrangements of genetic material between chromosome 4 and several other chromosomes have been associated with leukemias, which are cancers of blood-forming cells.