, Volume 27, Issue 6, pp 265-276,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 01 Apr 2010

Genome-wide microarray evidence that 8-cell human blastomeres over-express cell cycle drivers and under-express checkpoints

Abstract

Purpose

To understand cell cycle controls in the 8-Cell human blastomere.

Methods

Data from whole human genome (43,377 elements) microarray analyses of RNAs from normal 8-Cell human embryos were compiled with published microarrays of RNAs from human fibroblasts, before and after induced pluripotency, and embryonic stem cells. A sub database of 3,803 genes identified by high throughput RNA knock-down studies, plus genes that oscillate in human cells, was analyzed.

Results

Thirty-five genes over-detected at least 7-fold specifically on the 8-Cell arrays were enriched for cell cycle drivers and for proteins that stabilize chromosome cohesion and spindle attachment and limit DNA and centrosome replication to once per cycle.

Conclusions

These results indicate that 8-cell human blastomere cleavage is guided by cyclic over-expression of key proteins, rather than canonical checkpoints, leading to rapidly increasing gene copy number and a susceptibility to chromosome and cytokinesis mishaps, well-noted characteristics of preimplantation human embryos.

Capsule Over-expression of cell cycle drivers and lack of checkpoints render 8-Cell human blastomeres susceptible to genetic and chromosomal mishaps.