Chromosomal location of structural genes encoding murine immunoglobulin lambda light chains. Genetics of murine...

Area of Science:

• Immunogenetics
• Genomics
• Molecular Biology

Background:

• Immunoglobulin (Ig) structural genes encode essential proteins for the adaptive immune system.
• Previous research mapped kappa light chain genes to chromosome 6 and heavy chain genes to chromosome 12 in mice.

Purpose of the Study:

• To determine the chromosomal localization of murine lambda light (L) chain structural genes.
• To complete the chromosomal mapping of all immunoglobulin structural genes in the mouse.

Main Methods:

• Utilized a panel of 11 mouse x hamster somatic cell hybrids.
• Scored hybrid DNA for sequences homologous to cloned lambda DNA probes.
• Analyzed chromosome presence in hybrids correlating with lambda gene sequences.

Main Results:

• Six of eleven hybrids contained detectable murine lambda I and lambda II gene sequences in germline configuration.
• The remaining five hybrids lacked detectable murine lambda L chain gene sequences.
• Mouse chromosome 16 was present in all positive hybrids and absent in negative hybrids.

Conclusions:

• Murine lambda L chain structural genes are assigned to chromosome 16.
• This assignment completes the chromosomal mapping of Ig structural genes (heavy, kappa L, and lambda L) in the mouse.