Alleles are variant forms of a gene that are located at the same position, or genetic locus, on a chromosome. An allele frequency is calculated by dividing the number of times the allele of ...

Mayo Clinic's Precision Mouse Engineering Core in Minnesota makes embryonic stem (ES) cell-based gene-targeted mice available to researchers.

That difference is actually a survival benefit: The combination of two individuals' different MHC (major histocompatibility locus) genes gives their offspring an advantage in beating back disease ...