dbsnp is not per se required

prinia/design.py

@@ -240,7 +240,7 @@ def create_primers_bwa(bam_handle, variant=None, region=None):
 def find_best_bwa(bam, variant=None, region=None, accept_snp=False, field=None, max_freq=None, dbsnp=None):
     primers = []
     for primer in create_primers_bwa(bam, variant=variant, region=region):
-        if not accept_snp and max_freq is not None:
+        if not accept_snp and max_freq is not None and dbsnp is not None:
             prim = find_snps(primer, dbsnp, field)
             if prim.snp_freq <= max_freq:
                 primers.append(prim)

prinia/primerdesign.py

@@ -163,7 +163,7 @@ def main():
                                                              "(qualities will be sanger-encoded 40)")
 
     parser.add_argument('-R', '--reference', help="Path to reference fasta file", default=None, required=True)
-    parser.add_argument('--dbsnp', help="Path to DBSNP vcf", default=None, required=True)
+    parser.add_argument('--dbsnp', help="Path to DBSNP vcf", default=None, required=False)
     parser.add_argument('--primer3', help="Path to primer3_core exe", default=None, required=True)
     parser.add_argument('--bwa', help="Path to BWA exe", default="bwa")
     parser.add_argument('--samtools', help="Path to samtools exe", default="samtools")