Question

In a pedigree analysis, the diagram represents

• A. Unrelated mating
• B. Consanguineous mating
• C. Affected parents
• D. Siblings
• E. Non-identical twins

Answer 1

Answer: (B)

In pedigree analysis, consanguineous mating (marriage of blood relatives) is shown by two horizontal lines connecting square and circle. Mating is shown by one horizontal line connecting square and circle. Affected individuals are shown by shaded circle (affected female) and shaded square (affected male).

Siblings are shown by circle (female) and square (male) with vertical lines up from each sibling and then these vertical lines are connected with a horizontal line. Non-identical twins are shown by circle and square (depending upon their sex) joined by two slants at 60${}^o$angle. Thus, the above symbol shows consanguineous mating (marriage of blood relatives).