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Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography
Published on: August 11, 2016
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[Suspected pathogenic mutation identified in two cases with oculocutaneous albinism]
Jiangmei He1, Meiling Zheng, Guilin Zhang
1Department of Genetics, First Affiliated Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P. R. China. acc0351@163.com.
Summary
Genetic testing identified pathogenic mutations in the TYR gene in two couples with children affected by albinism, likely causing oculocutaneous albinism type 1 (OCA1).
Area of Science:
- Genetics
- Ophthalmology
- Dermatology
Background:
- Albinism is a group of inherited disorders characterized by a lack of pigment in the skin, hair, and eyes.
- Non-syndromic oculocutaneous albinism (OCA) and ocular albinism (OA) are distinct genetic conditions.
- Genetic mutations are the underlying cause of various albinism types.
Purpose of the Study:
- To identify genetic mutations responsible for albinism in two couples with affected offspring.
- To investigate genes associated with non-syndromic OCA types I-IV and OA type I.
Main Methods:
- Deep sequencing was performed on key albinism-related genes: TYR, OCA2, TYRP-1, MITF, SLC45A2, and GPR143.
- All exons of these genes were analyzed.
- Sanger sequencing was used to validate the sequencing results.
Main Results:
- A frameshift mutation (c.925_926insC) in the TYR gene was identified in both female carriers.
- A pathogenic nonsense mutation (c.832C>T) in the TYR gene was found in one male partner.
- Another pathogenic nonsense mutation (c.346C>T) in the TYR gene was identified in the other male partner.
Conclusions:
- The identified TYR gene mutation c.925_926insC (p.Thr309ThrfsX9) is strongly implicated as the cause of the Oculocutaneous Albinism type 1 (OCA1) phenotype.
- Mutations in the TYR gene are a significant cause of albinism in the studied families.
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