ix. Marriages between blood relatives are not suitable. Explain this brief
Answers
Answer:
different studies revealed that children born from parents who were closely related increases the risks of having a baby with potentially life-threatening birth defects.
Marrying within a family can lead to abnormalities in your future offspring. This is because within a family, certain genetic traits remain dormant and are known as recessive genes (they are not seen as a disease or condition).
When two people having the same genes marry and reproduce, these once dormant recessive (ineffective) genes double, making them more likely to cause genetic abnormalities in children.
Although, the fact that people who marry within the second generation are more susceptible is fairly true. But for eg. If your grandfather and parents have had marriages within the family, your children are at greater risk due to the overcrowding of the gene pool.
To explain better, think of it this way. If your grandfather had some recessive genes and he married someone in the family with those same recessive genes i.e. those once dormant genes become dominant (more likely to cause genetic abnormalities). Your parents then got married within the same family making the concentration of these recessive genes even more. Now when you marry someone within your family, this gene pool will further become dense with recessive genes, due to both your genes getting added to the pool, making the possibility of your children having genetic abnormalities very high.