SAMHD1 gene

SAM and HD domain containing deoxynucleoside triphosphate triphosphohydrolase 1

The SAMHD1 gene provides instructions for making an enzyme that helps cut (cleave) molecules called deoxynucleoside triphosphates (dNTPs) into their deoxynucleoside and triphosphate components. The dNTP molecules are needed for the replication and maintenance of the genetic material (DNA) in the body's cells, and the amount of available dNTPs must be tightly controlled for these functions to proceed normally. Invading viruses such as the human immunodeficiency virus (HIV) also need dNTPs in order to replicate themselves. The SAMHD1 enzyme helps regulate the amount of available dNTPs to both meet the needs of the body's cells and control viral infections.

At least 78 mutations in the SAMHD1 gene have been identified in people with Aicardi-Goutières syndrome, a disorder that involves severe brain dysfunction (encephalopathy), skin lesions, and other health problems. Research suggests that mutations in this gene may lead to production of a SAMHD1 protein that does not properly regulate the amount of available dNTPs. As a result, DNA maintenance is impaired, allowing DNA damage to accumulate in cells. Research suggests that this DNA damage may lead to cell signaling that inappropriately activates an immune response. As a result, the immune system attacks the body's own tissues and organs, causing inflammatory damage to the brain, skin, and other body systems that lead to the characteristic features of Aicardi-Goutières syndrome.

Cytogenetic Location: 20q11.23, which is the long (q) arm of chromosome 20 at position 11.23

Molecular Location: base pairs 36,889,773 to 36,951,708 on chromosome 20 (Homo sapiens Updated Annotation Release 109.20200522, GRCh38.p13) (NCBI)

Cytogenetic Location: 20q11.23, which is the long (q) arm of chromosome 20 at position 11.23
  • AGS5
  • DCIP
  • dendritic cell-derived IFNG-induced protein
  • HDDC1
  • Mg11
  • monocyte protein 5
  • MOP-5
  • SAM domain and HD domain 1
  • SAM domain and HD domain-containing protein 1
  • SBBI88