Genomics

Many studies are done each year attempting to investigate, analyze, or otherwise assay many different genetic properties such as mutation rates, human origins, disease genes, and the like. The studies usually are themselves highly precise, very technical, and completely reliant on the general information gathered through genomic studies prior to their investigations. Genomics is the branch of genetics that studies organisms in terms of their genomes (http://www.dict.org/bin/Dict). Without genomics and the information that it has provided in regard to DNA structure, gene format, gene order, and so forth it would be virtually impossible to conduct many modern investigations. Genomics has provided critical data on the mapping of genes, bioinformatics, genome organization, and gene expression, all of which will be discussed briefly in the paragraphs below.

Mapping genomes was and is one of the more "glamorous" aspects of genetics. The human genome project gets substantial funding and journalists never miss an opportunity to praise the accomplishment of a fully sequenced genome. But unlike many popular sciences, there is a large amount of substance behind the popular glitter. Mapping the genome is critical for a number of reasons, including basic ones such as improving genome comprehension and more specific goals such as discovering protein homologues and disease genes. In gene sequencing, the Maxim and Gilbert (base destruction) Method or (more frequently) the Sanger Method (involving dideoxy hybridization) can be used to map short segments of the genome. Mapping can be done through several methods other than direct sequencing. These include chromosomal banding (very low resolution), sequencing expressed sequence tags (better resolution but only covers 80% of the genome), Differential displacement (good for locating possible disease genes), and sequence hybridization analysis (excellent for discovering homologues), all of which have advantages besides simple being useful to mapping.

The search for protein homologues is an aspect of comparative genetics, and as has been stated can be investigated through hybridization analysis. In hybridization analysis synthetic ssDNA is annealed to source DNA. This, of course, only occurs at locations where the complimentary ssDNA is identical (or nearly so, depending on temperature). Through chromosomal walking large sequences of short DNA sequences can be compared to one another on the basis of DNA hybridization. This sort of comparison is useful in not just searching for protein homologues but also investigating human origins and disease models.

Bioinformatics involves the application of computer science and statistics to genetic information. The goal of bioinformatics is better data storage, and this is done in large part through Algorithms and databases. Algorithms are generally software programs that are used to tabulate data in a variety of ways. They can, for example, be used to determining LOD scores and distinguish exons and introns. Databases can be used to store information in a highly categorized manner accessible through multiple routes.

Finally, genomics is very important in forensics. The principles learned through genomics have been used to establish several types of DNA fingerprinting, including RFLP/VNTR, STR, and SNPs. These methods are used in both criminal and civil cases, and are becoming very common place in everything from homicides to paternity cases. They generally work by comparing genetic samples (hair follicles, blood, semen, etc) from a suspected individual with a control, be it a child's genetic information (in which case those patterns not inherited from the mother must be seen in the father) or bodily fluids found at a crime scene (in which case a simple match is sufficient).

In general, then, genomics is very important in modern society and will continue to be as genetics in general is pushed farther onto the scientific center stage. Without genomics much of what has been accomplished could not have been, and to believe that there are not more discoveries of similar magnitude is not appropriate.