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.
You could use a different name brand, and a different type of oil in your engine every oil change and it woudn't matter. Synthetic is definetly the way to go. Not that Conventional is bad or anything..... But Synthetic is great as it's reduces friction, cleaner engine, less break down etc. etc. etc. etc.