Genetic Perspective and Clinical Characteristic of First-Degree Relatives of Keratoconus: A Review
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Abstract
Keratoconus is a degenerative condition marked by corneal thinning and cone-shaped bulging, leading to impaired vision. Research highlights significant hereditary and environmental influences, with higher incidence among first-degree relatives. Familial clustering and high concordance in identical twins underscore a strong genetic component. Identifying corneal abnormalities in first-degree relatives is crucial for early diagnosis and intervention. This review covers twin, sibling, and parent studies, genetic inheritance patterns, clinical characteristics, and pathophysiology. Keratoconus is more common in monozygotic twins than dizygotic twins, with increased risk for those with affected parents or siblings. Recent genetic studies, including GWAS and SNPs, have identified several associated genetic loci, affirming the hereditary component. First-degree relatives display distinct corneal characteristics and overexpression of TLR2 and TLR4, linked to the innate immune system. Given the genetic risks, screening and awareness among first-degree relatives are essential for early detection.
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