 However, it is surprisingly not found in liver tissue where Vitamin A (retinol) is primarily stored.Because of its importance in Vitamin A transport, STRA6 mutations are more commonly associated with problems with eye such as a reduction in retinal thickness and shortening of the inner and outer segments of rod photoreceptors.Therefore, as might be expected, STRA6 mutations result in a number of different abnormalities of the eye such as Microphthalmia, Anophthalmia, and Coloboma.