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Histone Modifications in Telomeres[edit]

I removed this section from the main wikipedia page because it is likely only of interest to specialists (maybe just the author shilling their own work?) and the article is already too sprawling and hard to read.

The telomeres of human cells have been found to have a unique histone modification pattern, with the most enriched modifications being H2BK5me1 and H3K3me3 and the least enriched modifications being H3K36me3 and H3K9me3 [1]

Section too technical?[edit]

There is a Wikipedia notification for the "Human telomeres, cancer and ALT (Alternative lengthening of telomeres)" section, saying it is too technical. I am in high school biology, and found this section of the article to be exactly what I am looking for. If you have even the slightest background in Biology (which you probably would when reading this article), or are willing to look up some of the other terms, you should be fine. Just like with anything else. This is not nearly as technical as it could be. I suggest removing this notification. (talk) 05:31, 1 November 2012 (UTC)

The best that I can tell so far is that the chromazones are like fuzzy catiapillars who pick up all vibrations they are exposed to. If there are any new ones they are added to the chain and a copy of the addition is made. Now the telomeres are medical repaire. They for some reason are laid dormate and it is up to the individual to reactivate them. It is said if you smoke do not because the experience will be to intense for most people.I know from personal experience and I like rollacoster rides anyway.I sometimes spell words incorrectly so I will know your condition. Lately no one seems to care so I better learn how to spell. I am Steven Allen Bellmer... — Preceding unsigned comment added by (talk) 09:07, 14 November 2013 (UTC)

Chromosome ends replication problem[edit]

The information given in the "Shortening" section is not ok. Citing: "On the leading strand, DNA polymerase can make a complementary DNA strand without any difficulty because it goes from 5' to 3'." In fact, there is one difficulty resulting in sequence shortening and it is the same one as in the case of the lagging strand. The replication of the leading strand to be initiated, there must be synthetized an RNA primer as well. One is sufficient at the beginning of the new strand. Eukaryotic DNA is usually replicated from several origins of replication (ori) as stated in the article, so the RNA primers occuring in the middle of the chromosome are further converted to DNA by RNase, DNA polymerase and DNA ligase. However, the situation is different while replicating the 3' of template DNA molecule. RNA primer synthetized at the end of the chromosome will be degraded, but won't be converted into DNA, because there is no room for new primer from which the replication could start. Thus, both new DNA strands (lagging as well as leading) will lack a short sequence at their ends.Marian Varga (talk) 15:21, 8 February 2014 (UTC)

Telomere shortening and Cancer risk[edit]

There is a lot of information describing the role of telomerase and limitless replicative potential in cancer cells (see the Telomerase article). However, telomere shortening has been associated with aging & aging-related diseases, such as cancer. It would be interesting to include this as a separate topic under the cancer section.

Several studies indicate that shorter telomeres, particularly in immune cells, are a risk factor for cancer. Recent research has studied how lifestyle factors including diet, exercise & stress management can increase telomerase activity and telomere length (Ornish et al. 2013, Frattaroli et al. 2008). Also, the role of diet in cancer incidence & progression has been studied, particularly in prostate and colon cancer (Pellatt et al 2012, Mirabello 2009). A recent study found an association between dietary meat consumption and shortened colonocyte telomeres in rats (O’Callaghan et al. 2012). Telomere lengthening through lifestyle changes is an interesting topic of disease prevention research which could enhance this article. Whitneym89 (talk) 20:25, 9 February 2014 (UTC)

  1. ^ Rosenfeld, Jeffrey A; Wang, Zhibin; Schones, Dustin; Zhao, Keji; DeSalle, Rob; Zhang, Michael Q (31 March 2009). "Determination of enriched histone modifications in non-genic portions of the human genome.". BMC Genomics 10 (143): 143. doi:10.1186/1471-2164-10-143. PMC 2667539. PMID 19335899.  Unknown parameter |unused_data= ignored (help)