code: public GlResourceBuilder locus(final String glstring) throws GlClientException {
          alleles.clear();
          alleleLists.clear();
          haplotypes.clear();
          genotypes.clear();
          genotypeLists.clear();
          locus = client.createLocus(glstring);
          return this;
      }
docs: Return this gl resource builder configured with the specified locus.  If an allele has
  already been added to this builder, this call provides the locus operator ('<code>^</code>' character).
  The locus operator combines two or more genotype lists into a multilocus unphased genotype.
  
  @param glstring locus in GL String format, must not be null
  @return this gl resource builder configured with the specified locus
  @throws GlClientException if an error occurs