MYL1 and myopia: Because the retina is a neural tissue, the expression of numerous genes linked to cardiac muscle (MYBPC3, ACTC1, MYL3, MYH7, MYH7B) or to skeletal muscle (MYL1, SMYD1, TNNI2, MYH1B, ACTA1, TNNT3) presents a conundrum for explaining a mechanism for myopia progression.