def strip_alleles(possible_alleles, gene_call):
    """
    :param possible_alleles: list of possible allele strings (e.g. '*01, *02'...). Default is to *09, more than in IMGT
    :param gene_call: The current working call for the gene(s) in a given rearrangement
    :return: The same gene(s) stripped of any allelic information
    """

    # First remove allele strings
    for pa in possible_alleles:
        gene_call = gene_call.replace(pa, '')

    # Then ensure we're still dealing with unique gene calls
    genes = list(set(gene_call.split(',')))
    genes.sort()

    return ','.join(genes)