Video Transcript
Receiving medical counsel about the
possibility of transmitting one’s preexisting diseases to one’s partner is an
advantage of premarriage medical screening. What else is considered an
advantage of premarriage medical screening? (A) Choosing characteristics like
the eye color of the child before their birth. (B) Limiting the probability of
giving birth to a healthy child. (C) Avoiding the financial,
psychological, and social burdens that come with caring for a child suffering from
genetic diseases. (D) None of the answers are
correct.
Medical screening is done to detect
infectious and genetic diseases which can be passed from parents to their
offspring. Let’s go through the answer choices
to see which one is correct.
In answer choice (A), we’re unable
to choose certain characteristics like eye color before a child is born. We may have the technology to do
this, but this is generally not done for ethical reasons. Therefore, answer choice (A) is not
an advantage of premarriage medical screening.
Let’s look at answer choice (B) now
and describe how premarriage medical screening can be used to predict the
probability of giving birth to a healthy child. Let’s say we have a gene that we
abbreviate with the letter T. We have two alleles. The functional allele is given by
uppercase T, and the nonfunctional allele is given by lowercase t.
We can have three different
possible genotypes as shown here. Having two copies of the lowercase
t allele causes a disease, while having a single copy of uppercase T does not. If someone has a single copy of
both, they don’t have the disease but are carriers of the disease-causing
allele. When two heterozygotes have a child
together, there’s a chance that the child will be affected by the disease. We can see that here. 25 percent of the time, both
lowercase t alleles will be inherited, and the child will have this disease.
So, through premarriage medical
screening, we can screen the potential parents to see if they’re carriers. If they are, then they can choose
not to conceive a child. So premarriage medical screening
can be used to limit the probability of giving birth to a baby with a genetic
disease, which is the opposite of what answer choice (B) states. Therefore, this answer is
incorrect.
By limiting the probability of
having a child with a genetic disorder, potential parents can avoid the financial,
psychological, and social burdens that come with this. So the correct option is answer
choice (C), avoiding the financial, psychological, and social burdens that come with
caring for a child suffering from genetic diseases.