Inherited retinal disease (IRD) is one of the leading causes of blindness both in children and adults of working age. IRD encompasses a clinically and genetically heterogeneous group of disorders and over 250 genes have been implicated (RetNet, https://sph.uth.edu/retnet/). Clinical trials of treatment have been ongoing in North American/European countries. However, no effective treatment is available in daily clinic in East Asian countries, since there have been no well-characterized large cohort studies in East Asian population.

OBJECTIVE
The objective of the East Asia IRD studies is to establish a large cohort of East Asian Patients with IRD in the international multicenter studies.

PROJECTS
1. East Asia Occult Macular Dystrophy (EAOMD) Project
2. East Asia Stargardt (EAStar) Project

East Asia Occult Macular Dystrophy (EAOMD) Project

Occult macular dystrophy (OMD) first described in Japan by Prof Yozo Miyake is an inherited macular dystrophy characterized by a progressive visual impairment with an essentially normal fundus appearance.1-3 Confined macular dysfunction detected by macular electroretinograms (ERGs) is a key to diagnose this disorder.1-5 In 2010, linkage analyses of Japanese OMD families detected causative mutations in Retinitis pigmentosa 1-like 1 (RP1L1) gene and immunohistochemistry study in the retina of cynomolgus monkey demonstrated the RP1L1 protein expressed in the rod and cone photoreceptors.6 Since the discovery, a number of cases with RP1L1 mutations in East Asian have been reported.7,8 A Nationwide OMD project in Japan revealed the distinct microstructural phenotype of RP1L1-associated retinal disorder (Miyake’s disease) in 2016.9 It is known that OMD is one of the most prevalent IRDs in East Asian population, which is quite unique compared to European population. However, the characteristics of OMD have not been fully understood in the Asian context.

OBJECTIVE
The objective of the EAOMD is to characterize the clinical and genetic features in East Asian population with the standardized diagnostic criteria.

CHAIR OFFICE
NATIONAL INSTITUTE OF SENSORY ORGANS, NATIONAL HOSPITAL ORGANIZATION, TOKYO MEDICAL CENTRE
2-5-1, Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan

1) Kaoru Fujinami, MD, PhD
Study Chair, Principal Investigator
Email: k.fujinami@ucl.ac.uk

2) Takeshi Iwata, PhD
President, Global Eye Genetics Consortium
President, Japan Eye Genetics Consortium

3) Kazushige Tsunoda, MD, PhD
Principal Member, Japan Eye Genetics Consortium

4) Yozo Miyake, MD, PhD
Member, Japan Eye Genetics Consortium

LEADING INSTITUTES
PEIKING UNION MEDICAL COLLEGE HOSPITAL
1#Shuaifuyuan, Dongcheng District, Beijing 100730, China

1) Ruifang Sui, MD, PhD
Principal Investigator
Email: hrfsui@hotmail.com

2) Lizhu Yang, MD
Investigaror


SEOUOL NATIONAL UNIVERSITY BUNDANG HOSPITAL
173(baekchilsipsam)beo, Bundang-gu, Seongnam-si, Gyeonggi-do, South Korea

1) Se Joon Woo, MD, PhD
Principal Investigator
Email: sejoon1@snu.ac.kr

2) Kwangsic Joo, MD
Investigaror

REFERENCE
1. Miyake Y, Ichikawa K, Shiose Y, Kawase Y. Hereditary macular dystrophy without visible fundus abnormality. Am J Ophthalmol. 1989 Sep 15;108(3):292-9.
2. Miyake Y, Horiguchi M, Tomita N, Kondo M, Tanikawa A, Takahashi H, Suzuki S, Terasaki H. Occult macular dystrophy. Am J Ophthalmol. 1996 Nov;122(5):644-53.
3. Miyake Y, Tsunoda K. Occult macular dystrophy. Jpn J Ophthalmol. 2015 Mar;59(2):71-80.
4. Tsunoda K, Usui T, Hatase T, Yamai S, Fujinami K, Hanazono G, Shinoda K, Ohde H, Akahori M, Iwata T, Miyake Y. Clinical characteristics of occult macular dystrophy in family with mutation of RP1l1 gene. Retina. 2012 Jun;32(6):1135-47.
5. Fujinami K, Tsunoda K, Hanazono G, Shinoda K, Ohde H, Miyake Y. Fundus autofluorescence in autosomal dominant occult macular dystrophy. Arch Ophthalmol. 2011 May;129(5):597-602.
6. Akahori M, Tsunoda K, Miyake Y, Fukuda Y, Ishiura H, Tsuji S, Usui T, Hatase T, Nakamura M, Ohde H, Itabashi T, Okamoto H, Takada Y, Iwata T. Dominant mutations in RP1L1 are responsible for occult macular dystrophy. Am J Hum Genet. 2010 Sep 10;87(3):424-9.
7. Ahn SJ, Cho SI, Ahn J, Park SS, Park KH, Woo SJ. Clinical and genetic characteristics of Korean occult macular dystrophy patients. Invest Ophthalmol Vis Sci. 2013 Jul 18;54(7):4856-63.
8. Nakanishi A, Ueno S, Kawano K, Ito Y, Kominami T, Yasuda S, Kondo M, Tsunoda K, Iwata T, Terasaki H. Invest Ophthalmol Vis Sci. 2015 Nov;56(12):7243-9.
9. Fujinami K, Kameya S, Kikuchi S, Ueno S, Kondo M, Hayashi T, Shinoda K, Machida S, Kuniyoshi K, Kawamura Y, Akahori M, Yoshitake K, Katagiri S, Nakanishi A, Sakuramoto H, Ozawa Y, Tsubota K, Yamaki K, Mizota A, Terasaki H, Miyake Y, Iwata T, Tsunoda K. Novel RP1L1 Variants and Genotype-Photoreceptor Microstructural Phenotype Associations in Cohort of Japanese Patients With Occult Macular Dystrophy. Invest Ophthalmol Vis Sci. 2016 Sep 1;57(11):4837-4846.