Alu family A group of closely related DNA sequences arising from a single ancestral sequence (see gene family) and found dispersed and repeated many times within the genome of humans and other primates. Full-length Alu sequences are about 280 bp long, and many are cleaved by the restriction enzyme AluI (hence the name). The human haploid genome contains roughly 500 000 full-length copies of Alu, plus many partial Alu sequences, making it the most abundant single sequence in the entire genome and constituting a large proportion of the class of moderately repetitive DNA known as SINEs. Alu sequences occur in the nontranslated regions (introns) of genes and between genes and probably have no function. They are retrotransposons and can thus replicate themselves. The variations in structure and distribution of Alu sequences among primates can be used both to help track the evolutionary history of the genome and as genetic markers (see marker gene) for physical mapping.
More From encyclopedia.com
gene family , gene family A group of similar or identical genes, usually along the same chromosome, that originate by gene duplication of a single original gene. S… Pseudogenes , Pseudogenes are defective copies of functional genes. These may be partial or complete duplicates derived from polypeptide-encoding genes or RNA gene… Operon , Operon An operon is a genetic regulatory system found in prokaryotes and the bacterial viruses (bacteriophages ) that attack bacteria. It is a cluste… Methylation , DNA methylation is a mechanism used to regulate genes and protect DNA from some types of cleavage. It is one of the regulatory processes that are ref… Tandem Array , tandem array Repetitive DNA, where the repeating units are contiguous. Some genes of high copy number occur in tandem arrays e.g. ribosomal DNA in eu… Nomenclature , Like any other field in science, genetics has its own language. However, genetics is also a multidisciplinary field that encompasses expertise, and h…
About this article
Updated About encyclopedia.com content Print Article
You Might Also Like