A human clone containing a portion of the gene encoding several isoforms of the beta 1 subunit of voltage-dependent calcium channels was isolated and partially sequenced. The gene was mapped to chromosome 17 using the polymerase chain reaction with oligonucleotides that allowed the specific amplification of the human sequence in the human-rodent hybrids. A polymorphic dinucleotide repeat was identified within the gene and typed on a subset of the CEPH families. Using multipoint linkage analysis the most likely location of the beta 1 subunit gene is between D17S36 and NGFR on chromosome 17q11.2-q22.