The key to development: interpreting the histone code?

Developmental stages in multicellular organisms proceed according to a temporally and spatially precise pattern of gene expression. It has become evident that changes within the chromatin structure brought about by covalent modifications of histones are of crucial importance in determining many biological processes, including development. Numerous studies have provided evidence that the enzymes responsible for the modifications of histones function in a coordinated pattern to control gene expression in the short term and, through the transferral of these modifications by inheritance to their progeny, in the long term.     

From symbolism to information? – Decoding the gene code

‘Information’ and ‘code’ originated as technical terms within linguistics and information theory but are now widely used in genetics and developmental biology. Against this background, it is examined if coded information distinguishes genes from other information carriers, i.e., whether there are genetic words or sentences by virtue of the genetic code, and, if so, whether they have any semantic content. It is concluded that there is no genetic language with semantic content, but that the genetic code still enables unique language-like modes of transmission and interpretation of causal information.     

Human infectious diseases in the genomics era: where do we go from here?

Ripudaman K Bains is the editor of the Genome Biology special issue content on the ‘genomics of infectious diseases’, and introduces the collection in this editorial.     

Human gastrointestinal helminth infections: are they now neglected diseases?

Although over half the world's population might be infected by gastrointestinal (GI) helminths, their importance as therapeutic targets has been much underrated. GI helminths have only been recognized as causing considerable damage to individuals and to communities in the past 20 years, and global recognition of the problem only occurred within the past few years. As we move into the 21st century, there is a desire to undertake the challenging task of global control of GI helminths, while problems of drug resistance are discussed in the same breath. Today, we have tools that are effective for the task ahead, but these might only be available for a short time. Because of their effectiveness (both for control and as treatments for individuals), their simplicity of use and their excellent tolerability, there has been no incentive to develop new options. Unless there is a sustained effort in drug research and development, we might have to face a world without effective anthelmintics.     

Stress and the epigenetic landscape: a link to the pathobiology of human diseases?

Accumulating evidence points to a major role for chronic stress of cell renewal systems in the pathogenesis of important human diseases, including cancer, atherosclerosis and diabetes. Here we discuss emerging evidence that epigenetic abnormalities may make substantial contributions to these stress-induced pathologies. Although the mechanisms remain to be fully elucidated, we suggest that chronic stress can elicit heritable changes in the chromatin landscape that 'lock' cells in abnormal states, which then lead to disease. We emphasize the need to investigate epigenetic states in disease and links to stress and to consider how the knowledge gained through these studies may foster new means of disease prevention and management.     

Does the 'non-coding' strand code?

The hypothesis that DNA strands complementary to the coding strand contain in phase coding sequences has been investigated. Statistical analysis of the 50 genes of bacteriophage T7 shows no significant correlation between patterns of codon usage on the coding and non-coding strands. In Bacillus and yeast genes the correlation observed is not different from that expected with random synonymous codon usage, while a high correlation seen in 52 E. coli genes can be explained in terms of an excess of RNY codons. A deficiency of UUA, CUA and UCA codons (complementary to termination) seems to be restricted to the E. coli genes, and may be due to low abundance of the relevant cognate tRNA species. Thus the analysis shows that the non-coding strand has the properties expected of a sequence complementary to a coding strand, with no indications that it encodes, or may have encoded, proteins.     

Human grief: Is its intensity related to the reproductive value of the deceased?

Thurstone's method of comparative judgement was used to measured the intensity of grief that parents of high-, moderate-, and low-reproductive value were expected to experience at the death of male and female children of different ages. The results were correlated with reproductive values for male and female British Columbians and for !Kung Bushwomen. Grief ratings were more highly correlated with reproductive value than with age and more highly correlated with reproductive values of !King Bushwomen than with those of British Columbians. The correlations were higher for male- than for female-stimulus children. The correlations of female ratings with reproductive value were higher than male ratings with reproductive value, although not as high as expected. However, the correlation between grief ratings and reproductive value did not increase as the reproductive value of the raters declined.     

Human dignity: a guide to policy making in the biotechnology era?

This article explores the ways in which human dignity is used in debates about controversial biotechnologies, including biobanks, human gene patents, stem cell research and human cloning. Increasingly, human dignity is used as a form of general condemnation and as blanket justification for regulatory restraint. However, this use of human dignity marks a significant departure from the traditional, human-rights informed view of human dignity that has dominated bioethics debates for decades. In addition, on its own, it stands as dubious justification for policies that are aimed at constraining controversial biotechnologies.