Mutational screening of 10 genes in Chinese patients with microphthalmia and/or coloboma

[摘要] Purpose: To screen ten genes formutations in 32 Chinese patients with microphthalmia and/or coloboma. Methods: Genomic DNA was prepared from32 unrelated patients with microphthalmia (nine probands) and uvealcoloboma (23 probands). Cycle sequencing was used to detect sequencevariations in ten genes, including BMP4, VSX2, CRYBA4,GDF6, OTX2, RAX, SIX3, SIX6, SOX2,and LRP6. Variations were further evaluated in 96 unrelatedcontrols by using restriction fragment length polymorphism (RFLP) orheteroduplex-single strand conformation polymorphism (HA-SSCP)analysis. Results: In the ten genes, a novelc.751C>T (p.H251Y) in BMP4 was detected in a patient withbilateral microphthalmia and unilateral cataract. The c.751C>Tvariation is also present in his healthy brother (and possibly one ofthe normal parents). In addition, a novel c.608G>A (p.R203Q) in SIX6was identified in an internal control for optimizing experimentalconditions. The internal control was from a girl with typical aniridiaand an identified c.718C>T (p.R240X) mutation in PAX6,suggesting the c.608G>A variation in SIX6 was unlikely toplay a role in her ocular phenotype. The c.751C>T in BMP4and the c.608G>A in SIX6 were not present in the 96 normalcontrols. In addition, 16 nucleotide substitutions, including eightknown SNPs and eight new synonymous changes, were detected. Conclusions: Although the geneticetiology for microphthalmia and/or coloboma is still elusive, rarevariations in the related genes, such as c.608 G>A in SIX6and c.751C>T in BMP4, may not be causative. These resultsfurther emphasize the importance of careful clinical and geneticanalysis in making mutation-disease associations.

[学科分类] 生物化学/生物物理