Česká Genetická Banka

SCIENCE: 1. 3. 2013

SCIENCE: One Genome, Two Ontogenies

"The fascination of humans with the notion of multiple personalities (and morphologies) is perhaps best captured in Robert Louis Stevenson's 1886 tale of the Strange Case of Dr Jekyll and Mr Hyde. Land plants have been pulling off this trick for 475 million years, although perhaps to less acclaim. All of the roughly 300,000 extant species of land plants (1) engage in a complex life cycle that alternates between sporophytes (spore-producing organisms) and gametophytes (gamete-producing organisms). Biologists have long pondered how each species of land plant can maintain separate developmental programs that produce fundamentally dissimilar ontogenies and morphologies. On page 1067 of this issue, Sakakibara et al. (2) provide insights into the developmental and evolutionary origins of this alternation of generations." (...)

http://www.sciencemag.org/content/339/6123/1045.summary

 

SCIENCE: The Continuing Challenge of Understanding, Preventing, and Treating Neural Tube Defects

"Neural tube defects (NTDs) are debilitating birth defects involving the central nervous system (CNS). Despite recent advances, NTDs represent the second most common group of human birth defects. These defects arise when the complex process of early CNS development goes awry. Normally, the brain and the spinal cord begin to form as a flat sheet of cells that rolls up and closes to form a hollow neural tube. Failure in this rolling and sealing process results in an NTD, such as spina bifida. From animal models, we know of over 200 genes that regulate this process, with many more still likely to be discovered. Environmental factors also can have a profound influence on neural tube closure, as evidenced by the impact of folic acid on NTD prevalence. However, the mechanisms by which environmental factors affect the process of neural tube closure and their critical interaction with genetic factors remain largely a mystery." (...)

http://www.sciencemag.org/content/339/6123/1222002.abstract

 

NATURE: Replication stress links structural and numerical cancer chromosomal instability

"Cancer chromosomal instability (CIN) results in an increased rate of change of chromosome number and structure and generates intratumour heterogeneity^{1, 2}. CIN is observed in most solid tumours and is associated with both poor prognosis and drug resistance^{3, 4}. Understanding a mechanistic basis for CIN is therefore paramount. Here we find evidence for impaired replication fork progression and increased DNA replication stress in CIN⁺ colorectal cancer (CRC) cells relative to CIN⁻ CRC cells, with structural chromosome abnormalities precipitating chromosome missegregation in mitosis. We identify three new CIN-suppressor genes (PIGN (also known as MCD4), MEX3C (RKHD2) and ZNF516 (KIAA0222)) encoded on chromosome 18q that are subject to frequent copy number loss in CIN⁺ CRC. Chromosome 18q loss was temporally associated with aneuploidy onset at the adenoma–carcinoma transition. CIN-suppressor gene silencing leads to DNA replication stress, structural chromosome abnormalities and chromosome missegregation." (...)

http://www.nature.com/nature/journal/v494/n7438/full/nature11935.html

 

NATURE: Parental consent: Guarding children's genetic privacy

"Open sharing of genotype and phenotype information is crucial for advancing research into childhood diseases, but depends on consent…"

http://www.nature.com/nature/journal/v494/n7438/full/494430d.html

 

NATURE: Stem cells cruise to clinic

"In the seven years since their discovery, induced pluripotent stem (iPS) cells have transformed basic research and won a Nobel prize. Now, a Japanese study is about to test the medical potential of these cells for the first time. Made by reprogramming adult cells into an embryo-like state that can form any cell type in the body, the cells will be transplanted into patients who have a debilitating eye disease." (...)

http://www.nature.com/news/stem-cells-cruise-to-clinic-1.12511