A paper in press at Human Molecular Genetics (Lahola-Chomiak et al., https://www.ncbi.nlm.nih.gov/pubmed/30561643) reports the results of a collaboration led by Dr. Michael Walter, and involving the Lehmann and Allison labs. This work discovered the first causative gene for pigmentary glaucoma, a common subtype of glaucoma, which represents the leading cause of irreversible blindness worldwide.
Dr. Walter’s team first identified a mutation in the premelanosome (PMEL) gene in DNA samples from two Mennonite cousins before identifying additional PMEL mutations in a cohort of patients with pigmentary glaucoma. Molecular analyses demonstrate that these mutations alter the function of the PMEL protein, and CRISPR-CAS9 mutagenesis of pmel in zebrafish resulted in both pigment defects and glaucoma-like phenotypes. In parallel, colleagues at Harvard and the University of Flinders (Drs. Wiggs and Craig), identified PMEL mutations in additional pigmentary glaucoma cases, strongly supporting the role of PMEL mutations in PG. Overall, these results improve understanding of the etiology of a major form of blindness, with opportunities for novel approaches for diagnosing and eventually treating this common form of glaucoma.
Figure 1. Typical signs of pigmentary glaucoma (pigment granules on the corneal endothelium, heavy pigmentation of the trabecular meshwork, and iris trans-ilumination defects.
Figure 2. pmel CRISPR-generated zebrafish mutant demonstrating globe enlargement (a feature of congenital glaucoma in infants).
Nicole is working on her PhD thesis under two AVN members, Dr. Ian McDonald and Dr. Ted Allison. Congratulations to Nicole for receiving a CIHR Canada Graduate Scholarship to support her during her studies.
A recently published paper in PLoS Genetics (Hocking et al., March 2018) is the culmination of a long-standing collaborative project by two AVN labs (PIs: Ordan Lehmann and Andrew Waskiewicz). The group identified eight patients with tissue gaps in the superior portion of the iris, retina, and/or lens – a novel congenital disease the researchers termed Superior Coloboma. By using zebrafish to revisit ocular development, the authors discovered the superior ocular sulcus, a transient groove bisecting the dorsal retina and the potential origin of superior coloboma. Moreover, they showed how patterning cues control formation and closure of the sulcus and its developmental function in directing growing ocular blood vessels.
Lance (MacDonald Lab) recently received a Retina Foundation of Canada Clinical Research Grant that will support his research into novel causes of retinal and macular dystrophies.
Telodendria are delicate structures that connect photoreceptor cells to one another and allow for information to be shared laterally between them. Despite their discovery in the late 19th century, telondendria are not widely known or well characterized in vision science. Nicole Noel recently studied these poorly understood features of photoreceptors in the zebrafish retina during her Master’s thesis in the Allison lab. Her work has now been published in the Journal of Comparative Neurology, with one of her beautiful photos featured on the issue cover.
AVN needs a logo! AVN members, it’s time to get out your crayons. We’re having a contest and the winner gets a cash prize and will hopefully have their design displayed as our new logo.
Due: Jan 10th, 2018
Send your logo to: firstname.lastname@example.org
Please read these tips before starting: Logo tips
Good funding opportunity for AVN students conducting basic and clinical research.
See here for further info:
Nicole recently received an Alberta Innovates – Health Solution scholarship to fund her PhD research under the joint supervision of two AVN members – Dr. Ian MacDonald and Dr. Ted Allison. Way to go Nicole!
This graduate level course is open to graduate students with an interest in the broad field of ocular genetics. Individual lectures will be provided as background to supplement the discussion of pertinent papers and topics. Each session will be led by a local expert (currently 8) and cover principles of ocular genetics, development, function, and disease. The course marks will be 70% based on written answers to questions after each session and 30% for a final presentation and participation in class.
Course will be held in Katz 7-003B on Wednesday afternoons in the Winter term beginning Jan. 10th, 2018
Contact Lisa Trottier: email@example.com