Rafati N, Chen J, Herpin A, Pettersson ME, Han F, Feng C, Wallerman O, Rubin CJ, Péron S, Cocco A, Larsson M, Trötschel C, Poetsch A, Korsching K, Bönigk W, Körschen HG, Berg F, Folkvord A, Kaupp UB, Schartl M, Andersson L.

Proc Natl Acad Sci U S A. 2020 Sep 16:202009925. doi:10.1073/pnas.2009925117

Reconstruction of the birth of a male sex chromosome present in Atlantic herring.

A ~500-kbp region on Chr8 is sex-associated, and within it, two ~100 kbp windows are only found in males in a single copy. Thus the Chr8 is an X/Y pair. The Y chromosome does not lack genes present on the X chromosome. It is estimated that it evolved prior the divergence of the Atlantic and Pacific species 2 My ago.