ADAM9 gene

Overview

Gene (OMIM No.)	ADAM9 (#602713)
Function of gene/protein	Protein: A disintegrin and metalloproteinase domain 9 Plays a role in cell-cell matrix interaction Important for fertilisation, muscle development and neurogenesis
Clinical phenotype (OMIM phenotype no.)	Autosomal recessive cone-rod dystrophy: Cone-rod dystrophy 9 (#612775)
Inheritance	Autosomal recessive
Signs	Vessel attenuation Early onset posterior pole atrophy (including the macula) Some patients have a coloboma-like lesion in the macula Discrete white patches in the posterior pole and around the optic disc Mid-peripheral bone spicule pigmentation with RPE atrophy in advanced stages Optic disc pallor Early onset cataract (usually posterior sub-capsular)
Visual function	Reduced VA in 1st decade of life Dyschromatopsia Progressive peripheral VF loss
Systemic features	No extraocular features reported
Key investigations	Full field ERG: Relatively mild retinal dysfunction (cone-rod pattern) Pattern ERG: undetectable FAF: reduced AF in the posterior pole with a hyper-AF border at the temporal edge of atrophy OCT: outer retinal loss at areas of atrophy
Molecular diagnosis	Next generation sequencing Targeted gene panels (retinal) Whole exome sequencing Whole genome sequencing
Management	Ocular Management of cone-rod dystrophy
Therapies under research	None at present
Further information	OMIM

Hull S, Arno G, Plagnol V, Robson A, Webster AR, Moore AT. (2015) Exome sequencing reveals ADAM9 mutations in a child with cone-rod dystrophy [Internet]. Acta Ophthalmologica;93(5):e392–3
Parry, D.A., Toomes, C., Bida, L., Danciger, M., Towns, K.V., Mckibbin, M., Jacobson, S.G., Logan, C.V., Ali, M., Bond, J., Chance, R., Swendeman, S., Daniele, L.L., Springell, K., Adams, M., Johnson, C.A., Booth, A.P., Jafri, H., Rashid, Y., Banin, E., Strom, T.M., Farber, D.B., Sharon, D., Blobel, C.P., Pugh, E.N., Pierce, E.A. & Inglehearn, C.F. (2009) Loss of the Metalloprotease ADAM9 Leads to Cone-Rod Dystrophy in Humans and Retinal Degeneration in Mice. The American Journal of Human Genetics, 84 (5), pp.683–691
El-Haig WM, Jakobsson C, Favez T, Schorderet DF, Abouzeid H. Novel ADAM9 homozygous mutation in a consanguineous Egyptian family with severe cone-rod dystrophy and cataract. Br J Ophthalmol. 2014;98(12):1718-1723
Danciger M, Hendrickson J, Lyon J, et al. CORD9 a new locus for arCRD: mapping to 8p11, estimation of frequency, evaluation of a candidate gene. Invest Ophthalmol Vis Sci. 2001;42(11):2458-2465

Updated on January 18, 2021