@article{LauknerTruchetManukjanetal.2021, author = {Laukner, Anna and Truchet, Laura and Manukjan, Georgi and Schulze, Harald and Langbein-Detsch, Ines and Mueller, Elisabeth and Leeb, Tosso and Kehl, Alexandra}, title = {Effects of cocoa genotypes on coat color, platelets and coagulation parameters in French Bulldogs}, series = {Genes}, volume = {12}, journal = {Genes}, number = {7}, issn = {2073-4425}, doi = {10.3390/genes12071092}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-242745}, year = {2021}, abstract = {A nonsense variant in HPS3, c.2420G>A or p.Trp807*, was recently discovered as the cause for a brown coat color termed cocoa in French Bulldogs. Here, we studied the genotype-phenotype correlation regarding coat color in HPS3 mutant dogs that carried various combinations of mutant alleles at other coat color genes. Different combinations of HPS3, MLPH and TYRP1 genotypes resulted in subtly different shades of brown coat colors. As HPS3 variants in humans cause the Hermansky-Pudlak syndrome type 3, which in addition to oculocutaneous albinism is characterized by a storage pool deficiency leading to bleeding tendency, we also investigated the phenotypic consequences of the HPS3 variant in French Bulldogs on hematological parameters. HPS3 mutant dogs had a significantly lowered platelet dense granules abundance. However, no increased bleeding tendencies in daily routine were reported by dog owners. We therefore conclude that in dogs, the phenotypic effect of the HPS3 variant is largely restricted to pigmentation. While an effect on platelet morphology is evident, we did not obtain any indications for major health problems associated with the cocoa coat color in French Bulldogs. Further studies will be necessary to definitely rule out very subtle effects on visual acuity or a clinically relevant bleeding disorder.}, language = {en} } @article{ConradKehlMuelleretal.2023, author = {Conrad, David and Kehl, Alexandra and M{\"u}ller, Tobias and Klopfleisch, Robert and Aupperle-Lellbach, Heike}, title = {Immunohistochemical and molecular genetic analysis of canine digital mast cell tumours}, series = {Animals}, volume = {13}, journal = {Animals}, number = {10}, issn = {2076-2615}, doi = {10.3390/ani13101694}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-319199}, year = {2023}, abstract = {Grading, immunohistochemistry and c-kit mutation status are criteria for assessing the prognosis and therapeutic options of canine cutaneous mast cell tumours (MCTs). As a subset, canine digital MCTs have rarely been explored in this context. Therefore, in this retrospective study, 68 paraffin-embedded canine digital MCTs were analysed, and histological grading was assessed according to Patnaik and Kiupel. The immunohistochemical markers KIT and Ki67 were used, as well as polymerase chain reaction (PCR) for mutational screening in c-kit exons 8, 9, 11 and 14. Patnaik grading resulted in 22.1\% grade I, 67.6\% grade II and 10.3\% grade III tumours. Some 86.8\% of the digital MCTs were Kiupel low-grade. Aberrant KIT staining patterns II and III were found in 58.8\%, and a count of more than 23 Ki67-positive cells in 52.3\% of the cases. Both parameters were significantly associated with an internal tandem duplication (ITD) in c-kit exon 11 (12.7\%). French Bulldogs, which tend to form well-differentiated cutaneous MCTs, had a higher proportion of digital high-grade MCTs and ITD in c-kit exon 11 compared with mongrels. Due to its retrospective nature, this study did not allow for an analysis of survival data. Nevertheless, it may contribute to the targeted characterisation of digital MCTs.}, language = {en} }