Chromosome 1 is the largest of the 23 chromosomes, containing a greater number of nucleotides at its 85 loci than all other chromosomes. There are an estimated 4220 genes on chromosome 1, as discovered during the Human Genome Project around twenty years ago.

The short arm (p) of chromosome 1

The genes present on the short arm of chromosome 1 include:

• ACADM coding for acyl-Coenzyme A dehydrogenase, C-4 to C-12 straight chain
• COL11A1 coding for collagen, type XI, alpha 1
• CPT2 coding for carnitine palmitoyltransferase II
• DBT coding for dihydrolipoamide branched chain transacylase E2
• DIRAS3 coding for DIRAS family, GTP-binding RAS-like 3
• ESPN coding for espin and deficiency leading to autosomal recessive deafness 36
• GALE coding for UDP-galactose-4-epimerase
• GJB3 coding for gap junction protein, beta 3, 31kDa (connexin 31)
• HMGCL coding for 3-hydroxymethyl-3-methylglutaryl-Coenzyme A lyase (hydroxymethylglutaricaciduria)
• KCNQ4 coding for potassium voltage-gated channel, KQT-like subfamily, member 4
• KIF1B coding for kinesin family member 1B
• MFN2 coding for mitofusin 2
• MTHFR coding for 5,10-methylenetetrahydrofolate reductase (NADPH)
• MUTYH coding for mutY homolog (E. coli)
• NGF coding for nerve growth factor
• PARK7 coding for proteins which in autosomal recessive conditions may lead to early onset Parkinson disease, 7
• PINK1 coding for PTEN induced putative kinase 1
• PLOD1 coding for procollagen-lysine 1, 2-oxoglutarate 5-dioxygenase 1
• TSHB coding for thyroid stimulating hormone, beta
• UROD coding for uroporphyrinogen decarboxylase. This gene mutation is responsible for porphyria cutanea tarda

The long (q) arm of chromosome 1

The genes present on the long arm of chromosome 1 include:

• ASPM that determines brain size
• F5 coding for coagulation factor V (proaccelerin, labile factor)
• FMO3 coding for flavin containing monooxygenase 3
• GBA coding for glucosidase beta, glucosylceramidase and a gene whose mutation results in Gaucher's disease
• GLC1A or gene responsible for glaucoma
• HFE2 or a gene leading to juvenile hemochromatosis type 2
• HPC1 coding for a gene that predisposes for prostate cancer
• IRF6 that codes for a gene for connective tissue formation
• LMNA coding for lamin A/C
• MPZ that codes for myelin protein zero (Charcot-Marie-Tooth neuropathy 1B)
• MTR coding for 5-methyltetrahydrofolate-homocysteine methyltransferase
• PPOX coding for protoporphyrinogen oxidase
• PSEN2 coding for presenilin 2 (Alzheimer disease 4)
• SDHB coding for succinate dehydrogenase complex subunit B
• TNNT2 coding for cardiac troponin T2
• USH2A coding for a gene that predisposes to Usher syndrome 2A (autosomal recessive, mild)

Key for above depiction:

• Magenta and green: patterns of light and dark bands seen under light microscope
• Red: the centromere
• Yellow: areas that take on a variety of staining and are called heterochromatin

Further Reading

• All Chromosome 1 Content
• What is Chromosome 1?

Written by

Dr. Ananya Mandal

Dr. Ananya Mandal is a doctor by profession, lecturer by vocation and a medical writer by passion. She specialized in Clinical Pharmacology after her bachelor's (MBBS). For her, health communication is not just writing complicated reviews for professionals but making medical knowledge understandable and available to the general public as well.