showed that there was no significant change in CC in eyes with PXE compared with control eyes,  which is similar to the results obtained in the present study.
In a study by Yavas et al., there was no change in AL, LT, and ACD in eyes with PXE as compared to normal eyes,  the findings of which were similar to the results of the present study, except a significant increase in AL was observed in eyes with PXE.
PXE can be associated with considerable morbidity and significant mortality, with a highly variable phenotypic spectrum with both inter- and intrafamilial heterogeneity.9 The histology of PXE is characteristic.
Two among three patients described in this study were women and presented with skin lesions of PXE. In one patient, skin changes and asymptomatic mitral valve prolapse were found.
The earliest fundus finding of PXE is peau d'orange, which occurs as the result of the accumulation of yellow material in the RPE and is seen more in the temporal macula.
PXE should be considered for patients with the fundoscopic finding of angioid streaks.
In summary, the genotypes associated with an altered enzyme activity were associated with an earlier clinical manifestation of PXE symptoms in all 3 of the polymorphisms investigated.
Chronic oxidative stress could explain most of the structural and biochemical alterations observed in PXE. For the most relevant PXE lesions (i.e., alterations in extracellular matrix components, degradation and mineralization of elastic fibers, and neovascularization), the involvement of ROS has already been demonstrated (22, 33-35).
The results indicate that our sample has a sufficient size to detect associations with a power of 79%-90% for a relative risk of [greater than equal to]2.0 for the most frequent polymorphisms (minor allele frequency 25%-45%, significance a = 5%), assuming an additive or multiplicative model for PXE. Assuming a dominant or recessive model, our study had a power of 37%-59% or 16%-45%, respectively.
LD and haplotype blocks were evaluated in PXE patients and controls using Haploview 3.2 and PHASE v2.1.1 (30, 31).
In the present study, we evaluated the association between serum fetuin-A, calcium and phosphate, and the PXE phenotype to investigate the link between an absence or functional insufficiency of MRP6 and mineralization of elastic fibers in PXE.
The study cohort comprised 110 German patients with PXE and 53 unaffected first-degree family members from 96 nonconsanguineous families with an apparently autosomal recessive or sporadic mode of inheritance of the PXE phenotype.