| Modification Notes |
RBJ, also known as DNAJC27 (DnaJ homolog subfamily C member 27) or RABJS (Rab and DnaJ domain-containing protein), is a 273 amino acid member of both the small GTPase superfamily and the Rab family. Containing one J domain, RBJ is highly expressed in nervous system and reproductive organs, and may lack GTPase activity. Existing as three alternatively spliced isoforms, the RBJ gene is conserved in chimpanzee, dog, cow, mouse, rat, chicken and zebrafish, and maps to human chromosome 2p23.3. As the second largest human chromosome, chromosome 2 makes up approximately 8% of the human genome and contains 237 million bases encoding over 1,400 genes. A number of genetic diseases are linked to genes on chromosome 2. The lipid metabolic disorder sitosterolemia is associated with ABCG5 and ABCG8. An extremely rare recessive genetic disorder, Alström syndrome, is related to mutations in the ALMS1 gene. Chromosome 2 contains a probable vestigial second centromere as well as vestigial telomeres, which gives credence to the hypothesis that human chromosome 2 formed as a result of an ancient fusion of two ancestral chromosomes, which are still present in modern day apes. |