Gene vs DNA
The terms “DNA” and ‘gene’ are related, but they are not the same. There are some certain differences between these two terms but both are used in genetics very often. Both genes and DNA are considered as the genetic materials of many organisms and contain heredity information in almost all the organisms on Earth.
What is DNA?
DNA is a nucleic acid that contains heredity information, which is used in the development and functioning of all known organisms. Except some viruses, the major genetic material of all the other organisms is DNA. Human DNA contains about 3 billion bases of genes. Each human cell has 46 double stranded DNA.
A DNA molecule has two long chains of nucleotides which are coiled into a double helix. The nucleotide chains consist of four types of nucleobases called adenine, thymine, guanine and cytosine. The orders of these bases are different among individuals as well as among species. The backbone of the nucleotide chains is made of sugars and phosphate groups joined by ester groups. Eukaryotes store most of their DNA inside their nucleus while prokaryotes store their DNA in the cytoplasm.
What is a Gene?
Genes are functioning subunits of DNA molecules, which exist in nuclei and other certain cell organelles. Each gene contains a particular set of instructions which is usually used to code for a specific protein. A DNA molecule has many genes, and each gene consists of thousands or even hundreds of thousands of chemical bases. Number of genes depends on the DNA number in a particular cell and the numbers vary widely among organisms. Therefore, a gene or set of genes determines the differences between individuals within a species as well as differences between species.
Human genome consists of over 20,000 genes, and certain genes of humans are also found in other animals and even in certain plants. This is because the life on earth has evolved from simple to more complex organism and many of the genes responsible for basic metabolic processes were retained.
The composition of the genes can be changed by the process of mutation, thus results in more effective genes with improved functions. If two adjacent genes are carrying out the same function, one gene is free to replicate. This is how certain gene sets are evolved to control a particular function.
What is the difference between Gene and DNA?
• Genes are a specific segment of DNA.
• DNA molecule has two long chains of nucleotides while genes represent a specific region of those nucleotide chains.
• Within a cell, DNA is organized into structures called chromosomes.
• Human genome consists of over 20,000 genes. Each human cell has 46 double stranded DNA. Therefore, the amount of genes is higher than that of DNA of a single cell.
• Genes determine one or few traits while DNA determines many traits.
• When the DNA replicates, genes also replicate with it.