In the Human Genes for B-Globin,a Locus Control Region Is

Question

In the human genes for b-globin,a locus control region is characterized by
A) regulating the expression of the b-globin gene.
B) containing several DNAse I hypersensitive sites.
C) being about 15 kb in length.
D) acting upstream of the genes it affects.
E) All of these are correct.

Accepted Answer

A locus control region (LCR) is a regulatory region that is responsible for controlling the expression of genes within a given locus. In the case of the human b-globin genes, the LCR is located upstream of the genes and is about 15 kb in length. The LCR contains several DNAse I hypersensitive sites, which are regions of chromatin that are more accessible to cleavage by DNAse I than other regions. These hypersensitive sites are thought to reflect regions of the chromatin that are actively involved in controlling gene expression. Therefore, all of the given choices are correct.