Sharply reduced levels of transcript from both the bw+ allele in cis with the rearrangement and the bw allele on the homologous second chromosome.
abnormal eye color | dominant
bwV1 is recessive in D.melanogaster/D.simulans hybrids.
Malpighian tubule colour: wild-type. Eye colour: brown; mottled with darker spots that deepen in red color with age. Eye colour: pale orange; dark orange spots, with st1. Eye colour: pale orange; dark orange spots, with v1. RK1A.
bwV1 has visible phenotype, suppressible by Dp(2;2)Su(Pm)
Dp(2;2)Su(Pm) suppresses the bw phenotype in bwV1, leaving only the variegation; Dp(2;2)Su(Pm)/bwV1 flies have variegated red eyes.
Extra Y chromosome, as with other variegated browns, suppresses brown color, giving red eye sparsely speckled or splotched with darker spots. Amount of wild-type eye color also responds to fourth-chromosome constitution; 4/C(4) > C(4) = 4/4 > 4/0, with the first approaching wild type and the latter nearly bw (Lindsley and Rokop). Generally lethal homozygous and in combination with other brown-Variegateds. Heterozygotes fully viable and fertile.