Understanding Gene Linkage: One Opinion about Shedding Light on Genetic Inheritance
Linkage is very important when it comes to the determination of the inheritance of certain traits as far as genetics is concerned and as a result is an important factor when dealing with genetics as compared to the simple Mendelian genetics. What many people picture in their minds is that genes are individually inherited markers, all of which have the same likelihood of being transmitted. That is not the case, though; genes inherited on the same chromosome are linked and most likely to be inherited together—this is what is known as linked genes.
Understanding of the Genetics of Gene Linkage:
Chromosomes are made up of thousands of gene; each gene has fixed location on a chromosome called locus. In meiosis, an important event is distinguished as crossing over, where segments are swapped between homologous chromosomes. On the other hand, alleles for genes which are located near each other in a chromosome, have tendency not to be separated during crossing over thus, resulting in linked genes.
For instance, if two genes come in a specific form and are situated adjacent to each other on a chromosome, they will kind of ‘move together’ and be passed on from one generation to another. This goes against independent assortment where every gene would be expected to have the same chance of being inherited with other genes. Knowledge of Gene linkage is very important in predicting the mode of inheritance and consequently the Genetic disorders.
Mapping of genes and linkage analysis:
The gene linkage has been important in aid of mapping of the genomes. More precisely, if the recombination events between two genes are frequent, it is assumed that they are close to each other. It enables scientists to make genetic maps that show the locations of genes on chromosome to enable comparison of distance. Such advancement has recommended discoveries for human genetics, as well as individualized medicine.
Implications for Health and Disease:
Linkage analysis has also played an important role of analytical tool in medical research. If the researchers map the clustering patterns of the genes associated with particular traits or diseases, it becomes much easier for the medical professionals to diagnose diseases such as cystic fibrosis, Huntington’s disease, and various types of cancer , among others. Knowledge of gene linkage, apart from helping to identify these diseases, also creates opportunities for possible treatments and even prevention.
The Future of Gene Linkage Research:The Future of Gene Linkage Research:
This paper shows that even as knowledge of gene linkage increases, more complex behaviors of linked genes are unravelled. Newer technologies that have emerged with respect to gene editing such as CRISPR also improve the prospect of understanding gene linkage and its consequences. By deconvoluting these genetic associations, we come closer to what precision and individualized medicine and treatment could mean for each one of us.
Author: Olivia Harrington
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