RNAs are the direct products of genes, and these small RNAs can bind to other specific messenger RNA (mRNA) molecules and either increase or decrease their activity, for example by preventing an mRNA from producing a protein.
What causes stretch marks? Stretch marks are caused when the skin rapidly stretches as a result of sudden growth or weight gain. The stretching causes the middle layer of skin (dermis) to tear, allowing the deeper skin layers to show through, forming stretch marks. The dermis contains strong, inter-connected fibres that allow your skin to stretch as your body grows.
Excessive rapid weight gain and pregnancy are the two most common risk factors. Other risk factors include the conditions described above that predispose the skin to developing stretch marks. Striae are rarely painful or itchy. They do not produce troublesome symptoms. They begin as linear red streaks and eventually mature into linear white lines.