ZingPath: Mendelian Genetics

Genetic Inheritance is a very complex concept that revolves around the transmission of genes from a set of parents to their child. This transmission can have several combinations that will impact the genetic characteristics that are expressed in the individual. These genes are carried through microscopic thread-like structures called chromosomes. Humans have 46 chromosomes that are paired up with one another to create 23 sets. Within these sets, an individual receives all the instructions for their characteristic traits, as well as, one specific set of chromosomes that will determine if the person will be male or female.

As stated above, this genetic make-up relies on the instructions of the genes passed down to an individual from his parents. These genes found within chromosomes are linked together to from a twisted double strand called deoxyribonucleic acid or DNA. With this transmission, an individual will receive a gene from his father and a gene from his mother to create a set. Except in co-dominance situations, this set will contain only one of the following combinations: one dominant and one recessive gene, two dominant genes, or two recessive genes. This combination will be reflected in the child's appearance, gender, and other inherited traits. Within these three combinations it is important to understand the differences between a recessive and dominant gene. When paired with the dominant gene, the recessive gene is not expressed, and that gene will not show its appearance in the child. In contrast, if a child receives two recessive genes from his parents, the gene expressed will be recessive.

Although a recessive gene may not be exhibited in the appearance of an individual, the DNA still retains the combination of both. This set will be of significance in the future transmission of genes from parents to offspring. These intricate structures of genetics are the tools used in creating the different combinations that make every person unique.