Cloning and characterization of the mouse alpha globin cluster and a new hypervariable marker

Area of Science:

• Genomics
• Molecular Biology
• Evolutionary Biology

Background:

• The alpha-globin gene cluster plays a crucial role in oxygen transport.
• Understanding the genomic organization surrounding gene clusters is vital for deciphering gene regulation and evolution.

Purpose of the Study:

• To isolate and characterize a 95-kb mouse genomic region encompassing the entire alpha-globin gene cluster.
• To identify and analyze novel genetic elements within this region, including regulatory elements and hypervariable regions.

Main Methods:

• Isolation of overlapping cosmid clones to reconstruct the genomic contig.
• Characterization of the cloned DNA sequence to identify genes and regulatory elements.
• Comparative analysis of genomic distances between mouse and human alpha-globin clusters.

Main Results:

• A 95-kb contiguous DNA segment containing the mouse alpha-globin cluster was successfully isolated and characterized.
• The contig includes the embryonic (zeta) and adult (alpha) globin genes, the N-methylpurine-DNA glycosylase (MPG) gene, an alpha-globin regulatory element (mHS-26), and a novel hypervariable region (mouse alpha-HVR).
• The mouse alpha-HVR contains a variable number tandem repeat (VNTR) array with a G+C-rich 35-bp repeat unit, sharing a core sequence with human alpha-gene cluster HVRs.

Conclusions:

• The characterized mouse genomic region provides a comprehensive view of the alpha-globin gene cluster and its flanking elements.
• The identified mouse alpha-HVR is a significant finding, potentially serving as a valuable evolutionary and genetic marker due to its sequence homology with human counterparts.
• Comparative genomic analysis reveals distinct organizational differences between mouse and human alpha-globin clusters.