It is genetic - in my family there is no history of it as it is a recessive gene but my mum and dad were both carriers. In Scotland up to 13% of the population has red hair, but around 40% of the population is thought to carry the recessive gene responsible for the world's rarest natural hair colour.
On the other hand, synthetic base oil molecules are chemically controlled, which provides increased ï¬ lm strength and lubricity over petroleum oils. The performance qualities of base oils have a marked impact on the performance qualities of the ï¬ nished product.
Synthetic oil is used as a substitute for lubricant refined from petroleum when operating in extremes of temperature, because, in general, it provides superior mechanical and chemical properties to those found in traditional mineral oils.he technical advantages of synthetic motor oils include: 1  Better low-and high-temperature viscosity performance at service temperature extremes. 2  Better (higher) Viscosity Index (VI). 3  Better chemical and shear stability. 4  Decreased evaporative loss. 5  Resistance to oxidation, thermal breakdown, and oil sludge problems.