Complex sentence: Heterodisomy (Heterozygous) indicates a meiosis I error, whereas isodisomy (homozygous) indicates either a meiosis II error or postzygotic duplication.
Split into simpler sentences: Heterodisomy (Heterozygous) indicates a meiosis I error. Isodisomy (homozygous) indicates either a meiosis II error or postzygotic duplication.