Question

Talk to the senior biology teacher in your school find out if there are diseases which are passed on from parents to the offspring. Find out how these are carried and also if these diseases can be treated. For this you can also visit a doctor

Answer 1

Genetic traits can be passed through families in several distinct patterns. The most common patterns are the following:

Dominant genetic diseases are caused by a mutation in one copy of a gene. If a parent has a dominant genetic disease, then each of that person’s children has a 50% chance of inheriting the disease. Dominant diseases can also occur spontaneously; this happens when a random mutation in one gene occurs at conception. Examples of dominant genetic diseases include Achondroplasia and Huntington disease. For some dominant genetic diseases, there may be specific DNA tests available.

Recessive genetic diseases. When both parents are carriers of the same recessive disease, there is a 25% chance that the pregnancy will inherit the trait from both parents and have the disease, a 50% chance that the pregnancy will inherit the trait from only one parent and be a carrier, or a 25% chance that the pregnancy will not inherit the trait from either parent and will not be a carrier or have the disease.

Sex-linked genetic diseases affect males and females differently.  This is a smaller set of diseases related to gene mutations on the X or Y chromosomes. Some common examples include hemophilia and color-blindness. Depending on your family history, testing for a sex-linked genetic disease may be available.

Multifactorial traits occur due to many complex interactions and combinations of maternal, environmental and genetic influences. The most common birth defects are members of this category, including congenital heart defects and cleft lip. Almost 1 child in 150 is born with a congenital heart defect and 1 in 500 with cleft lip. Another multifactorial condition is spina bifida, a type of an open neural tube defect. Spina bifida occurs in approximately 1 or 2 in 1000 births. Taking the vitamin folic acid (folate) helps reduce the chance of having a baby with spina bifida. In most cases predictive genetic testing is not available for multifactorial traits, however a family history assessment may provide more accurate recurrence risks.