It is a condition that is affected by an abnormality in an individual’s DNA. Defects can be as small as a single-base mutation in just one gene, or they can include the addition or subtraction of entire chromosomes.
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There are various types of genetic disorders. The way in which the disorder is obtained can help determine the risks it will have on pregnancy and the risk of recurrence it will recur incoming children. It is very dangerous that the baby with a birth defect from a genetic abnormality may be raised when:
- The parents have a different child with a genetic disorder.
- There is a family story of a genetic disorder.
- One mother has a chromosomal abnormality.
- The fetus has abnormalities observed on ultrasound.
What Are The Types Of Genetic Disorders?
Chromosomes are stick-shaped structures which are occurred in the middle of each cell in the body. Each cell has 46 chromosomes classified in 23 pairs. When a chromosome is abnormal, it can create health problems in the body. Abnormal chromosomes most often occur as a result of an error during cell division.
Chromosome abnormalities often result due to one or more of these:
- Errors when dividing of sex cells (meiosis)
- Errors during dividing of different cells (mitosis)
- Exposure to substances that affect birth defects (teratogens)
Single Gene Defects:
A single gene disorder is produced by variations (or mutations) in the DNA sequence of a specific gene. The DNA variations affect the product that the gene codes for—usually a protein—causing it to be changed or missing. The features of each disorder are linked to the particular gene that is affected and the job that the protein has in the body.
Some genetic disorders are so dangerous that children who have them are very sick or cannot survive after birth. Others are relatively easy to manage, and with proper care, people who have them have very fulfilling lives. The chances of a good outcome are much higher if the state is identified soon after birth, or even before.
Multifactorial inheritance indicates that “many factors” (multifactorial) are involved in effecting a birth defect. The factors are normally in both genetic and environmental, where a combination of genes from both mothers and fathers, in addition to unknown environmental factors, produce the feature or condition. Usually, one gender (either males or females) is affected more often than the other in multifactorial traits.
There seems to be a different “threshold of expression”, which indicates that one gender is more likely to show the problem over the other gender. For example, hip dysplasia is nine times more common in females than males.
A teratogen is any agent that produces an abnormality following fetal illness during pregnancy. Teratogens are usually discovered after an increased prevalence of a special birth defect. For example, in the early 1960s, a drug is known as thalidomide was utilized to treat morning sickness.
Exposure of the fetus through this early stage of development resulted in cases of phocomelia, a congenital malformation in which the hands and feet are connected to abbreviated arms and legs.
Teratogens can also be seen at home or in the workplace. The impact is related to the type of agent, dose and duration, and time of exposure. The first half of pregnancy is the most exposed. To know more details you can prefer Genetic Disorders Journal which provides you more information.