Conversion of an allelic combination defined in a selection formula into the
vector listing the alleles present (alleles that must be in the homozygous
state appear 2 times, 1 time for heterozygous).
Usage
extractAlleleComb(xVect)
Value
the list of alleles that must be present in the genotype to match
the input allelic combination
Arguments
xVect
allelic combination extracted from a selection formula.