Report on Ocular Melanosis Research Project

August 3, 2005

Simon Petersen-Jones
Lexi Mentzer
Michigan State University
Tel: 517-353-3278

Samples received

DNA Samples: Thus far, we have 210 DNA samples from Cairn Terriers, of which 96 are from dogs affected with Ocular Melanosis, and the remainder are from relatives of dogs with Ocular Melanosis (OM). We have pedigree information on 240 dogs, and have linked many of them together to better analyze the mode of inheritance of the disease.

Enucleated Eyes

Since January we have received 6 additional enucleated eyes.

Gene mapping project

We have sent 94 samples to the Veterinary Genomics Laboratory at UC Davis from Cairn terriers within our extended pedigree of Cairns with ocular melanosis for genotyping. The initial phase of running a microsatellite array analysis is complete along with the allele scoring for each of the chromosomal markers. The next step is to process the data collected using a computer program that can detect linkage of a portion of a chromosome with disease status. Once that is complete, the next step will be determined by what is shown from this initial processing.

Histological analysis

(no updated news in this section)

Culture of abnormal cells from ocular melanosis

Lexi has established a collaboration with a researcher experienced in culturing cells. The first step to culture normal iris melanocytes is underway, with preliminary success. Once this has been achieved we will then be ready to try and culture cells from an ocular melanosis affected eye. We will then need to wait until an enucleated eye becomes available. It is important that the eye is handled in a special way so we will need to contact the veterinarian involved to make sure that they are willing to help us.

What we need

We always need blood samples to use for DNA extraction from affected and related Cairns, accompanied by pedigrees and details of eye examinations.

We need enucleated eyes. It is important that we are contacted before they are removed so that we can ensure that the eye is handled in an appropriate manner for the part of the project we intend to use the eye for.

Important Note from HRCC

Dr. Petersen-Jones will present an, “Ocular Melanosis Update,” at the CTCA Education Day on Friday, October 7th. He and Lexi Mentzer will also screen dogs eyes for OM on Friday and Saturday. Please refer to your CTCA Specialty packets or go to for dates and times. To schedule an appointment to have your dogs eyes examined, please contact Pam McDonald at or 631-324-1779. For more information, or if you have questions, please contact Linda Heiner at or 760-630-4460.