Question

The $DNA$ fingerprinting analysis of four family members is shown below.

Study the band pattern obtained and assign each family member to $W, X, Y$ and $Z$. Choose the correct option.

• A. $W$ - father $X$ - mother $Y$-child $Z$ - paternal uncle
• B. $W$-child $X$ - father $Y$-mother $Z$ - maternal uncle
• C. $W$ - father $X$-child $Y$ - mother $Z$ - paternal uncle
• D. $W$ - child $X$ - father $Y$ - maternal uncle $Z$ - mother.

Answer 1

Answer: (C)

$DNA$ fingerprinting ($DNA$ profiling) is a technique of determining nucleotide sequences of certain areas of $DNA$ which are unique to each individuals. $DNA$ fingerprinting can help to distinguish one human being from another with exception of monozygotic twins. Individuals with highest number of matching $DNA$ bands are considered closest.
In the given analysis, $X$ has bands similar to both $W$ and $Y$; upper band is common between $X$ (child) and $Y$ (mother) while lower band is common between $X$ and $W$ (father). $Z$ has a band similar to $W$ (upper band) while it has no similarity with $X$ and $Y$. This indicates that $Z$ is a relative of $ W$ and can be paternal uncle of $X$.