Number of mouse V genes

The germline of BALB/c mice contains only two VA genes [56,57], and this appears true for other inbred mouse strains [58]. Feral mouse species also have a limited number of VK genes ranging from three to six [58], 

A similarly high estimate for mouse VK genes was made by Zeelon et al. [76]. 

Hybridization kinetics was used to measure the ratio of total k to VK21 mRNA in mouse spleen. This approach suggested the expression of 280 gene families and a total of approximately 2000 VK genes (assuming approximately seven genes per family). 

As noted above, Zeelon et al. [76] have estimated the germline VK repertoire to be one to two thousand genes, and Livant et al. [73] have estimated the germline VH repertoire to consist of 1000 or more genes. These higher estimates, if accurate, raise the possibility that the expressed V genes represent a fraction of the potential germline pool of V sequences. 

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