When researchers analyzed the remains of Tsar Nicholas II of Russia and his family,they found that the suspected Tsar and his living great-grandniece Xenia differed at nucleotide position 16169 in the mitochondrial DNA.Retesting the remains showed that for this site in the mitochondrial genome,the purported Tsar had thymine (T)in some samples and cytosine (C)in others.The most likely cause of this finding is
2-14-2013
A)the samples were too old.
B)incomplete dominance.
C)pleiotropy.
D)heteroplasmy.

Question

Quizplus · Accepted Answer

Heteroplasmy is when different copies of mitochondrial DNA exist within a single individual or sample. This can lead to variation in nucleotide positions, as seen in the case of Tsar Nicholas II and Xenia. The finding of T and C at nucleotide position 16169 suggests that the sample was heteroplasmic, with some copies of the mitochondrial genome containing T and others containing C.

When Researchers Analyzed the Remains of Tsar Nicholas II of Russia