The inheritance of most human qualities is complicated. They may be governed by a single gene with several alleles or by several genes. Pleiotropy (one gene, several effects) and epistasis may add to the complexity (gene-gene interactions). Mutations in one or a few genes cause many genetic diseases. The impact of a given mutation depends on what other mutations are present in the genome. In addition, environmental factors can play a role in disease development.
Our genetics research focuses on understanding how mutations in specific genes lead to disease and developing new therapies for genetic disorders. Genes are the building blocks of DNA - the language of life. Changes in or missing genes can cause serious health problems. However, many diseases that affect many people are due to changes in multiple genes occurring at the same time. Epigenetics is the study of these heritable changes that are not caused by changes in the DNA code itself, but rather by changes in the way that the DNA is packaged into chromosomes and interpreted by the cell. These epigenetic changes can influence when and where a gene is activated during development, allowing organisms to adapt to their environment without altering the underlying DNA sequence.
One purpose of our research is to understand how alterations in the activity of specific genes leads to particular diseases. This requires studying many different types of cells, including skin cells, blood cells, and lung cells. We also need to use specialized laboratory techniques to identify the exact change in each gene involved in each disorder.
Genes have a big role in determining traits and inheritance. The physical and functional components of heredity are known as genes. Genes are the biological molecules that are passed from parent to offspring. They provide the material for proteins and other cellular components. A gene is the specific DNA sequence that determines an individual's phenotype, or outward appearance and behavior. Genes can be found in all living organisms, but they cannot survive outside the body. They are made up of two strands of polymers, called deoxyribonucleic acid (DNA). Each gene has a copy called a gene template, which is contained within each cell of the organism. The information to make proteins is encoded by the nucleotide sequence of the gene template. This information is passed on from generation to generation through replication of the gene template during reproduction.
In genetics, an inheritance pattern is said to be dominant if the genetic trait is expressed even if it is not given a "1" by any of the genes at either end of the gene pair. For example, if one parent is black and the other white, their offspring will be black or white depending on what gene is given a "1" by each parent. If one parent is white and the other black, there will be no color change because both genes are missing.
Although a single gene may code for a given physical attribute, that gene might exist in several versions, known as alleles. Each of an organism's parents contributes one allele to each of its genes. Alleles result in either dominant or recessive phenotypes (physical forms of a characteristic). If one parent carries two alleles for a trait, they will pass on this information to their offspring. The offspring will be half dominant or half recessive depending on how the alleles are paired.
For example, if a parent has the BB genotype at a locus where the B allele codes for a red pigment production and the b allele does not, then the child will have the BB phenotype and produce no red pigment. If the parent has the BB genotype at a different locus where the B allele codes for white pigment production and the b allele does not, then the child will also have the BB phenotype and produce no red pigment. In contrast, if a parent has the BB genotype at both loci where the B allele codes for pigment production and the b allele does not, then the child will have the RB phenotype and produce a mixture of red and white pigment.
Thus, the inheritance pattern of two dominant alleles is called "BB". Two recessive alleles are "rr" and two alleles of any type at a given locus are called "ss".
The mutant allele's expression in relation to the normal allele might be classified as dominant, co-dominant, or recessive. For single-gene illnesses, there are five fundamental types of inheritance: autosomal dominant, autosomal recessive, X-linked dominant, X-linked recessive, and mitochondrial. These categories apply whether the illness is caused by a change in one gene or two genes on separate chromosomes.
For example, an individual with brown eyes and hair because they have brown pigment alleles for both xl and axial tissues, such as skin, would be considered as having a dominant phenotype for these traits. An individual who was completely white due to lack of pigment in their skin and hair but had blue eyes would be considered as having a recessive phenotype for eye color. If an individual has dark skin and hair but also has blue eyes, this would indicate that they have a mixed phenotype with some features of each of the two parents. Because there is evidence of melanin production in their skin cells, this person would not be considered as having a true phenotype of either dominant or recessive, but rather as having a co-dominant trait.
In conclusion, an inheritance pattern can only be determined based on the mode of transmission of a genetic disorder from parent to child. If you and your partner are able to have children together, then you will need to determine which pattern applies to your family history so that you will know how to plan for future pregnancies.