The First Neocentric, Discontinuous, and Complex Small Supernumerary Marker Chromosome Composed of 7 Euchromatic Blocks Derived from 5 Different Chromosomes.

Background: The majority of small supernumerary marker chromosomes (sSMCs) are derived from one single chromosome. Complex sSMCs instead consist of two to three genomic segments, originating from different chromosomes. Additionally, discontinuous sSMCs have been seen; however, all of them are derived from one single chromosome.