write introduction and overview about DNA, Gene and mutation. Also, what is the mutations types. where we can find the mutation information on the internet.
I wrote a paper that answer there questions but I want someone who can edit mine and add information on it since I didn’t talk about everything.
write introduction and overview about DNA, Gene and mutation. Also, what is the mutations types. where we can find the mutation information on the internet. I wrote a paper that answer there question
Introduction and Overview Studying human DNA and genetics doesn’t stop in understanding the connections between different groups of people or where a person’s ancestors might have come from. Studying DNA can help understanding the genetic basis behind human disease even though some genetic diseases are not treatable but discover them early can help improve the patient life or reduce the pain or the suffer. Human genome is the complete set of nucleic acid sequences encoded as a chemical called deoxyribonucleic acid, or DNA for short. DNA molecules are made of two twisting, paired strands, often referred to as a double helix and each strand is made of four chemical units called nucleotide bases (A, G, C, T). The information in the DNA is stored as a code of four base pairs which are adenine (A), guanine (G), cytosine (C), and thymine (T) which comprise the genetic “alphabet” . The bases exist as pairs: adenine to thymine and guanine to cytosine that needed to build the entire human body. DNA consists of two parts coding and non-coding regions. Coding DNA is the genes that produce protein within the genome, while non-coding DNA can be formed by genes that produce different types of RNA such as mRNA, tRNA or rRNA but they do not translate into proteins. Only 1% of the DNA sequence is coding for proteins, the remining 99% of the sequence represent non-coding part. The non-coding parts or the junk DNA act as regulatory that specify when genes are turned on and off and it can act as a regulator that control gene functionality. Genetic information of a cell stored in the form of DNA, which is then transcribed to form RNA and then translated to generate protein. Nucleotides from the DNA are transcribed to their complementary forms on RNA, which are then read as codons or groups of three, to code for specific amino acids in a large protein this is known as the central dogma of molecular biology. If one of the nucleotides on the DNA is mutated like for example turning thymine-based into an adenine-based (3’- CT/AC- 5) then that will affect the RNA sequence and ultimately the protein that follows, the protein will change from Glu to Val in this case. So, we can say that mutations are mistakes in a cell’s DNA that ultimately lead to abnormal protein production. However, while many mutations cause disease, others are silent or normal; that is, they have no discernible effect on the phenotype of an individual. Polymorphism is term that usually used for neutral mutation and pathogenic term used to describe mutation that change the phenotype of individual and cause disease or medical conditions. Gene Mutations and Genomic Variations Mutation or genetic variations is sudden and abrupt changes in nucleotide sequence of the DNA of an organism. Mutations can affect single DNA base pair or a large number of base pairs that includes multiple genes. The two things that can specify the consequences of gene mutations on health are the place where this mutation happens and if the mutation change the functionality of the gene coding protein. The types of mutations are single nucleotide polymorphism (SNP), insertion, deletion and duplication. The single nucleotide polymorphism, frequently called SNPs is the most popular type among people and caused by change in one nucleotide base in the DNA sequence. SNPs occur approximately every 1000 bases in the overall human population which result about 5 million SNPs in a person’s genome. If the results of SNP substitute the amino acid by another and change the protein function, this mutation called missense mutation and may lead to diseases. However, if the change results from changing the amino acid by stop codon, protein may function improperly or not at all and that called nonsense mutation. Deletion mutation happens when one or more bases in the DNA are deleted. For instance, AUGGGACGA becomes AUGGACGA, the G base pair has been deleted from the sequence. The opposite of deletion is insertion mutation where one base pair added into the DNA sequence. Any DNA variant not resulting in an amino acid change is considered as neutral or called silent mutation for instance GCT, GCC, GCA and GCG genes all code for alanine, so any change in the third position of the codon does not alter the amino acid. Therefore, neutral mutation does not have any harmful or beneficial effect on the organism. However, pathogenic are diseases that are caused by loss-of function gene products. Based upon the American College of Medical Genetics and Genomic, variants consider pathogenic two evidence happened, (a) the variant has been reported previously and associated with disease, or (b) the variant has not been reported previously but it is expected to cause the disease. The common diseases resulting from gene mutations are. Mutation Data and Information on the Internet Mutations databases play a crucial role in research, diagnostic and genetic health care. One of the comprehensive resources of mutation information at the National Center for Biotechnology Information is ClinVar which is a database that is freely accessible to the public. ClinVar database acts as a public archive where reports of the relationships among human variations and phenotypes, with supporting evidence are kept. The database holds 880,704 submitted records from 1,329 submitters, representing 560,748 unique variants with total of 32191 genes. The interpretations in ClinVar impact more than 55,000 genes and for variants that affect a single gene 7224 genes are represented in ClinVar. Another powerful database is Single Nucleotide Polymorphism database links different polymorphism and varying clinical mutations to other National Cancer Biotechnology Information resource (NCBI). The database serves as a central repository for all genetic variations (Smigielski et al., 2000). SNP can be searched directly or through other resources of the NCBI. Direct search can be performed through a submitter handle or laboratory, identification method used, the level of variation among the population studied, or through the submission of new batches (Smigielski et al., 2000). The Human Gene Mutation Database (HGMD) is one of the largest review resources for disease-causing mutations that freely available to registered users. The database contains over 260,000 mutation entries and over 10543 genes that manually curated and obtained from over 57,000 scientific literature. The mutations in the HGMD are either mutations associated with human inherited disease or mutations associated with disease reported in the literature . The Online Mendelian Inheritance in Man (OMIM) is another available database that attempts to record Pathogenic variation. The database contains 4,145 gene with mutation- disease associated. The database classifies the variations into four classes Single gene disorders and traits, Susceptibility to complex disease or infection, Non-diseases and Somatic cell genetic disease class. There are 3,764 gene-mutations cause 5,440 Single gene disorders phenotype, 501 gene-mutations cause 693 complex disease such as cancer, 116 gene-mutations causes 147 non-disease phenotypes and 127 genes associated with 226 variations cause somatic cell genetic disease [.