New insights into the evolution of the W chromosome in Lepidoptera

It is generally accepted that the W chromosome in moths and butterflies (Lepidoptera) has evolved in a common ancestor of Tischeriidae and Ditrysia. Several species of these clades were examined via comparative genomic hybridization to determine the presence of the W chromosome. In addition, in five selected genes their Z-linkage was tested by qPCR. The conserved synteny of the Z chromosome across Tischeriidae and Ditrysia, along with the W chromosome absence in the lower ditrysian families Psychidae and Tineidae, suggests a possible independent origin of the W chromosomes in these two lineages