358

26

Medicine and Disease

Bacterial Multiresistance

It is becoming increasingly widely perceived that one of the greatest threats to human

health is the increasing ability of microbes, especially bacteria, to resist antibiotics. ¹¹

This resistance is a rather obvious consequence of the inept use of antibiotics, ¹² but

there has been little success in effectively overcoming it. One difficulty is the rapidity

of the change. Analysis has shown that it occurs by the addition and rearrangement

of resistance determinants and genetic mobility systems, rather than by gradual mod-

ification of the genome (Sect. 14.4.2). ¹³

26.2

Noninfectious Diseases

Many diseases have no clear genetic signature, or they depend in a complex way on

genetic sequence. In cancer (cf. Sect. 14.5), for example, any relationship between

gene and disease must be highly complex and has so far eluded discovery in any

definitive sense. Mutations may be important, but the changes in protein levels are

equally striking. Both gene and protein chips are important here. ¹⁴

In this section we merely give some flavour of how bioinformatics is being applied

to tackle medical problems. The goal is always to construct the gigantic table of cor-

relations adumbrated in the introduction to this chapter. To render the task tractable,

usually a small but meaningful subset of the table is constructed. The examples

chosen illustrate typical approaches.

Osteoarthritis is a common chronic arthropathy occurring in elderly people. Lin

et al. (2018) aim to identify genetic differences between osteoarthritis synovial mem-

brane cells with and without inflammation. Differentially expressed genes (DEGs)

were identified and compared with the molecular targets of drugs commonly use

for the treatment of osteoarthritis, found by text mining. The comparison revealed

that the DEGs were primarily extracellular and predominantly involved cytokine and

cytokine activities.

Inflammatory response to thermal injury. The aim of Yang et al. (2007) was

to elucidate the role played by the liver in the response to burn injury. Therefore,

transcriptional data were obtained from liver samples taken from rats subjected to

burn injury immediately after the injury and at epochs up to 24 h later. The DEGs

were identified.

11 Summers (2002, 2006).

12 Kepler and Perelson (1998), Hermsen et al. (2012).

13 Shapiro (1992).

14 An example of the lack of a simple genetic cause of disease is illustrated by the fact that the

same mutations affecting the calcium channel protein in nerve cells are observed in patients whose

symptoms range from sporadic headaches to partial paralysis lasting several weeks. This is further

evidence in favour of Wright’s “many gene, many enzyme” hypothesis as opposed to Beadle and

Tatum’s “one gene, one enzyme” idea.