Clinical and genetic aspects of albinism

V.V.&nbsp;Kadyshev, S.A.&nbsp;Ryazhskaya, O.V.&nbsp;Khalanskaya, N.V.&nbsp;Zhurkova, R.A.&nbsp;Zinchenko Research Center for Medical Genetics, Moscow, Russian Federation Albinism is a clinically and genetically heterogeneous group of hereditary diseases whose pathogenesis is mediated by impaired synthesis of melanin which results in its partial or total loss. Reduced melatonin level clinically manifests as skin, hair, and ocular hypopigmentation. Ocular presentations include hypopigmentation/lack of pigmentation of eye fundus and iris, foveal hypoplasia, low vision, nystagmus and strabismus, photophobia, iris transillumination, and asymmetrical decussation of nerve fibers at the optic chiasm. However, albinism can be a part of more complex genetic syndromes, e.g., Hermansky-Pudlak syndrome or Chediak-Higashi syndrome. These disorders should be identified as early as possible to start therapy to prevent life-threatening conditions. Partial albinism with ocular, skin or hair hypopigmentation not associated with melanogenesis (e.g., Griscelli syndrome, Waardenburg syndrome, Aland Island eye disease, etc.) also occurs. Each case of albinism requir es an accurate molecular genetic diagnosis to provide a personalized treatment approach, predict life expectancy and health status, and plan pregnancy. Keywords: albinism, Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, hypopigmentation, clinical polymorphism, genetic heterogeneity. For citation: Kadyshev V.V., Ryazhskaya S.A., Khalanskaya O.V. et al. Clinical and genetic aspects of albinism. Russian Journal of Clinical Ophthalmology. 2021;21(3):175–180 (in Russ.). DOI: 10.32364/2311-7729-2021-21-3-175-180. </p

Emulsion sheet doublets as interface trackers for the OPERA experiment

New methods for efficient and unambiguous interconnection between electronic position sensitive detectors and target units based on nuclear photographic emulsion films have been developed. The application to the OPERA experiment,that aims at detecting Vμ⇋Vτoscillations in the CNGS neutrino beam,is reported in this paper. In order to reduce background due to latent tracks collected before installation in the detector,on-site large-scale treatments of the emulsions (“refreshing”) have been applied. Changeable Sheet (CSd) packages,each made of a doublet of emulsion films,have been designed,assembled and coupled to the OPERA target units (“ECC bricks”). A device has been built to print X-ray spots for accurate interconnection both within the CSd and between the CSd and the related ECC brick. Sample emulsion films have been extensively scanned with state-of-the-art automated optical microscopes. Efficient track-matching and powerful background rejection have been achieved in tests with electronically tagged penetrating muons. Further improvement of in-doublet film alignment was obtained by matching the pattern of low-energy electron tracks. The commissioning of the overall OPERA alignment procedure is in progress