def parse_lookup_table(lookupfile):
    """Parse the lookup table that contains AB genotypes."""
    ab_geno = {}
    with open(lookupfile, 'r') as l:
        for line in l:
            tmp = line.strip().split(',')
            snp = tmp[0]
            # add the line to ab_geno
            ab_geno[snp] = tmp
    return(ab_geno)