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A new and innovative method developed by the researchers at the EMBL-EBI, or The European Molecular Biology Laboratory’s European Bioinformatics Institute analyzes RNA sequence and lets the scientists detect previously unknown sub-types of cells. The discovery represents a giant step forward for single-cell genomics and it creates order out of what used to be considered seeming chaos.
What Is RNA?
All of the life on Earth uses three different forms of biological molecules and each one serves a very specific purpose within a cell. Proteins are the powerhouse and carry out a diverse array of roles, while nucleic acids, DNA, and RNA carry the genetic coding information that can be inherited from one generation to the next.
RNA stands for ribonucleic acid, and it is a polymeric molecule composed of one or more nucleotides. A person can think of an RNA strand like a chain, with a nucleotide at each link. Each nucleotide is composed of a base, a ribose sugar and a phosphate.
RNA is produced in the nucleus of a cell and can also be located in the cytoplasm. There are three primary types of RNA and these are messenger, transfer and ribosomal. Although it is single stranded, it can bend and twist into three dimensional shapes and hairpin loops. When these shapes occur, the nitrogenous bases bind to each other. Adenine pairs with uracil and guanine pairs with cytosine. The hairpin loops are most commonly witnessed in RNA molecules like messenger RNA and transfer RNA.
The structure of an RNA nucleotide is very much like that of DNA nucleotides, with the main difference being that the ribose sugar in RNA has a hydroxyl group that is not present in DNA. RNA plays a pivotal role in the pathway from DNA to proteins. During the transcription process, an RNA copy of a segment of DNA is made. This resulting strand can then be read by a ribosome to form a protein.
What Is DNA?
DNA or deoxyribonucleic acid is made of chemical building blocks called nucleotides and is located in the nucleus of cells. These building blocks are composed of three parts; a phosphate group, one of four nitrogen bases and a sugar group. To form a strand of DNA, nucleotides are linked into chains with the sugar and phosphate groups alternating.
The four types of nitrogen bases found in nucleotides are thymine, guanine, cytosine and adenine. The order of these bases will determine what biological instructions are contained within that particular strand of DNA. DNA can make a copy of itself. Both strands need to open up and make a copy of each other and become two strands of DNA. Hence, each new strand has one copy of the old DNA, from where the copy came from.
The Human Genome Project has estimated that each human has around 20,000 and 25,000 genes. Each person has two copies of each gene, one is inherited from the mother and the other is inherited from the father. These genes are mostly similar in all individuals, but a small number of genes are slightly different between people and this is what constitutes the basis for paternity testing and DNA testing.