The central dogma of biology explains how our DNA is expressed, from DNA to RNA and RNA to protein. Transcriptomics is the study of RNA expression level or a transcriptome. A transcriptome is the sum total of all the RNA and their quantity in a cell or a population of cells. [1] There are many factors that can influence the number of transcripts in our body such as environmental conditions and cell type.
Figure 1: Central dogma [2] Transcriptomics is the study of the transcriptome, which is the exploration of RNA expression
CLCN1 expressions within human
Human protein atlas is a useful database for exploring gene expression profiles from past human tissue sampling. Below is an example of a gene expression profile found when searching the CLCN1 datasets. This expression panel shows CLCN1 expression across predominantly in skeletal muscle tissues and a low level of expression in the testis. This allows for direct comparison between tissue types. It not only provides us to gain an insight into the role of CLCN1 in different cell types, but also in how it might influence diseases in these different tissues.
GEO Profiles is a another useful database, derived from GEO Datasets. Due to the prevalence of CLCN1 expression testis compare to other organs (like lung or liver), there have been several studies on the specific expression of CLCN1 in patients with myotonia congentia . Below is an example of a study with mice with laminin-211. Laminin-211 is a major constituent of the skeletal muscle basement membrane. It stabilizes skeletal muscle and influences signal transduction events from the myomatrix to the muscle cell[2]. Mice lines with laminin 211 knock and had minimal CLCN1 expression. This decreased expression is displayed below on the heat map. Genes with high expression in a particular genotype are displayed in pink, no difference in expression in black, and decreased expression in green compared to other samples.
[1] National Human Genome Research Institute. (2015). Transcriptome Fact Sheet. Retrieved March 9, 2017. https://www.genome.gov/13014330/ [2] Durbeej, M. (2015). Laminin-alpha2 chain-deficient congenital muscular dystrophy: pathophysiology and development of treatment. Curr. Top. Membr. 76, 31–60. doi: 10.1016/bs.ctm.2015.05.002