Redheads need more anesthesia to go under?

I put this as a question mark because I'm not so sure about this...They're going to draw these kinds of conclusions from a sample of 20, all of them from one American towns?

See:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1362956/

"[FONT=&quot]: The desflurane requirement in redheads (6.2 volume-percent [95% CI, 5.9 - 6.5]) was significantly greater than in dark-haired women (5.2 volume-percent [4.9 – 5.5], [/FONT]P[FONT=&quot] = 0.0004). Nine of 10 redheads were either homozygous or compound heterozygotes for mutations on the melanocortin-1 receptor gene.[/FONT][FONT=&quot]Conclusions: Red hair appears to be a distinct phenotype linked to anesthetic requirement in humans that can also be traced to a specific genotype."[/FONT]

I am still waiting to see a larger study, but there are quite a few more with more participants all indicating the same. Some indicating significant differences.

Here are a couple:



"Increased Sensitivity to Thermal Pain and Reduced Subcutaneous Lidocaine Efficacy in Redheads"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1692342/

"We evaluated pain sensitivity in red-haired (n=30) or dark-haired (n=30) women"

Conclusion:

"Red hair is the phenotype for mutations of the melanocortin 1 receptor. Our results indicate that redheads are more sensitive to thermal pain and are resistant to the analgesic effects of subcutaneous lidocaine. Mutations of the melanocortin 1 receptor, or a consequence thereof, thus modulate pain sensitivity."



"Genetic variations associated with red hair color and fear of dental pain, anxiety regarding dental care and avoidance of dental care."

https://www.ncbi.nlm.nih.gov/pubmed/19571053

"The authors enrolled 144 participants (67 natural red-haired and 77 dark-haired) aged 18 to 41 years in a cross-sectional observational study."

Conclusion:

"Dentists should evaluate all patients, but especially those with naturally red hair, for dental care-related anxiety and use appropriate modalities to manage the patients' anxiety."



"Anesthetic efficacy of the inferior alveolar nerve block in red-haired women."

https://www.ncbi.nlm.nih.gov/pubmed/23146638

"One-hundred twenty-four adult female subjects (62 red haired and 62 dark haired) participated in this study."

Conclusion:

"Red hair and the MC1R gene were significantly linked to higher levels of dental anxiety but were unrelated to success rates of the IAN block in women with healthy pulps."