I am usually not interested in celebrities, and even less about the gossips surrounding their private lives. I couldn't care less what their blood type or astrological sign is. But when it comes to mitochondrial DNA, I can think of several good reasons for which I would want to know that of some celebrities.
Mitochondrial DNA is a tiny yet essential part of our genome. Mitochondria produce the energy of each and every of our body's cells. Some types of mitochondria are more efficient than others, which is why some people are generally more energetic than others. MtDNA might influence such things as stamina, physical resistance, physical power, the speed and efficiency at which energy is produced and released by the body, or the ability to regenerate from exhaustion.
I am wondering whether some mtDNA haplogroups (or some specific SNP's) are found more frequently among high-level athletes, and whether there is a difference between the type of sport (as in the alleles of the ACTN3 gene favouring either sprinter vs long-distance runner).
That's not all. MtDNA also influences the body pH, including the brain's pH. Higher pH (more alkaline) is associated with better conductivity-transmission between neurons, higher IQ and lower risk of psychiatric disorders such as schizophrenia or bipolar disorder. Does that mean that the great minds are more likely to work on some types of mtDNA than others ?
As each mutation in the short mtDNA sequence can have a considerable influence on any of this, knowing the full sequence of famous people, especially athletes and intellectuals and great business/political leaders can prove very instructive. Just knowing the main haplogroup (e.g. H) without the deep subclade and private mutations is virtually useless.
The mtDNA of monarchs is not interesting in this case, as their fame is not based on special abilities but on hereditary rights.