Heterogonesis describes the segregation of parental genomes into distinct cell lineages in the dividing zygote. [1] [2]
Fertilisation occurs when an ovum fuses with a sperm, forming a zygote. Normally, the genomes of the two parents assort into two diploid bi-parental daughter cells. In a heterogoneic cell division, the genome of only one parent assorts into a single daughter cell following the formation of a tripolar (rather than the normal bipolar) spindle apparatus. [3] Heterogonesis allows for chromosomal segregation to occur in a dispermic fertilisation which may subsequently result in chimerism or sesquizygosis.
The term heterogonesis was coined in 2016 by Destouni and Vermeesch who observed the phenomenon in bovine zygotes. [1] The word is derived from the Greek meaning "different parental origin".
References
- ^ a b Destouni, Aspasia; Esteki; Catteeuw; Tšuiko; Dimitriadou; Smits; Kurg; Salumets; van Soom; Vermeesch, Joris (2016). "Zygotes segregate entire parental genomes in distinct blastomere lineages causing cleavage-stage chimerism and mixoploidy". Genome Research. 26 (5): 567–578. doi: 10.1101/gr.200527.115. PMC 4864459. PMID 27197242.
- ^ Gabbett, M.T.; Laporte, J.; Sekar, R.; Nandini, A.; McGrath, P.; Sapkota, Y.; Jiang, P.; Zhang, H.; Burgess, T.; Montgomery, G.W.; Chiu, R. (2019). "Molecular support for heterogonesis resulting in sesquizygotic twinning" (PDF). New England Journal of Medicine. 380 (9): 842–849. doi: 10.1056/NEJMoa1701313. PMID 30811910. S2CID 73512149.
- ^ Destouni, Aspasia; Vermeesch, Joris (2017). "How can zygotes segregate entire parental genomes into distinct blastomeres? The zygote metaphase revisited". BioEssays. 39 (4). doi: 10.1002/bies.201600226. PMID 28247957. S2CID 3813188.