OCA é uma doença autossômica recessiva da biossíntese de melanina que leva à perda total ou parcial de melanina na pele, folículos pilosos e olhos. Isso se deve a mutações em genes que codificam enzimas responsáveis pela síntese de melanina. Os sintomas clínicos e o curso da doença mostram uma variabilidade pronunciada, isso se deve a diferentes mutações genéticas que afetam vários pontos ao longo da via da melanina. Algumas das manifestações incluem nistagmo, hipopigmentação e translucidez da íris, pigmentação reduzida da retina, acuidade visual reduzida, etc. Os pacientes são propensos a efeitos deletérios da luz ultravioleta e, portanto, suscetibilidade aumentada para desenvolver ceratose actínica, carcinoma de células escamosas e carcinoma basocelular.
A utilidade clínica deste painel é:
| GENE | OMIM DISEASES | INHERITANCE* | % GENE COVERAGE (20X) | HGMD** |
| AP3B1 | Hermansky-Pudlak Syndrome |
AR |
100 |
34 of 35 |
| AP3D1 | Hermansky-Pudlak Syndrome, Ocular Albinism |
AR |
99.69 |
5 of 5 |
| BLOC1S3 | Hermansky-Pudlak Syndrome |
AR |
97.87 |
2 of 4 |
| BLOC1S6 | Hermansky-Pudlak Syndrome |
AR |
99.48 |
2 of 2 |
| DTNBP1 | Hermansky-Pudlak Syndrome |
AR |
99.96 |
4 of 4 |
| EPG5 | Immunodeficiency With Cleft Lip/Palate, Cataract, Hypopigmentation, And Absent Corpus Callosum, Vici Syndrome |
AR |
98.98 |
73 of 73 |
| GPR143 | Ocular Albinism, Nystagmus, X-linked Recessive Ocular Albinism |
X,XR,G |
96.52 |
– |
| HPS1 | Hermansky-Pudlak Syndrome |
AR |
99.98 |
68 of 68 |
| HPS3 | Hermansky-Pudlak Syndrome |
AR |
99.92 |
20 of 21 |
| HPS4 | Hermansky-Pudlak Syndrome |
AR |
99.7 |
30 of 30 |
| HPS5 | Hermansky-Pudlak Syndrome |
AR |
99.88 |
32 of 32 |
| HPS6 | Hermansky-Pudlak Syndrome |
AR |
99.87 |
39 of 41 |
| LRMDA | Oculocutaneous Albinism |
AR |
– |
– |
| LYST | Chediak-Higashi Syndrome |
AR |
99.98 |
117 of 117 |
| MC1R | Oculocutaneous Albinism, Familial Melanoma, Large Congenital Melanocytic Nevus |
AR |
– |
– |
| MITF | Coloboma, Osteopetrosis, Microphthalmia, Macrocephaly, Albinism, And Deafness, Tietz Syndrome, Waardenburg Syndrome |
AD,AR |
100 |
72 of 72 |
| MLPH | Griscelli Syndrome |
AR |
100 |
7 of 7 |
| MYO5A | Griscelli Syndrome, Neuroectodermal Melanolysosomal Disease |
AR |
100 |
10 of 10 |
| OCA2 | Oculocutaneous Albinism |
AR |
100 |
310 of 312 |
| RAB27A | Griscelli Syndrome |
AR |
100 |
54 of 55 |
| SLC24A5 | Oculocutaneous Albinism |
AR |
99.75 |
28 of 28 |
| SLC38A8 | Foveal Hypoplasia |
AR |
100 |
16 of 16 |
| SLC45A2 | Oculocutaneous Albinism |
AR |
100 |
157 of 159 |
| TYR | Oculocutaneous Albinism |
AR |
99.77 |
437 of 455 |
| TYRP1 | Oculocutaneous Albinism |
AR |
100 |
64 of 64 |
**HGMD: Número de mutações clinicamente relevantes de acordo com HGMD
Kubasch, A. S., & Meurer, M. (2017). Okulokutaner und okulärer Albinismus [Oculocutaneous and ocular albinism]. Der Hautarzt; Zeitschrift fur Dermatologie, Venerologie, und verwandte Gebiete, 68(11), 867–875. https://doi.org/10.1007/s00105-017-4061-x
Grønskov, K., Ek, J., & Brondum-Nielsen, K. (2007). Oculocutaneous albinism. Orphanet journal of rare diseases, 2, 43. https://doi.org/10.1186/1750-1172-2-43
Kamaraj, B., & Purohit, R. (2014). Mutational analysis of oculocutaneous albinism: a compact review. BioMed research international, 2014, 905472. https://doi.org/10.1155/2014/905472
Yang, Q., Yi, S., Li, M., Xie, B., Luo, J., Wang, J., Rong, X., Zhang, Q., Qin, Z., Hang, L., Feng, S., & Fan, X. (2019). Genetic analyses of oculocutaneous albinism types 1 and 2 with four novel mutations. BMC medical genetics, 20(1), 106. https://doi.org/10.1186/s12881-019-0842-7
Okulicz, J. F., Shah, R. S., Schwartz, R. A., & Janniger, C. K. (2003). Oculocutaneous albinism. Journal of the European Academy of Dermatology and Venereology : JEADV, 17(3), 251–256. https://doi.org/10.1046/j.1468-3083.2003.00767.x
Summers CG. Albinism: classification, clinical characteristics, and recent findings. Optom Vis Sci. 2009 Jun.
Goldberg, R. A., Lally, D. R., & Heier, J. S. (2015). Oculocutaneous albinism. JAMA ophthalmology, 133(3), e143518. https://doi.org/10.1001/jamaophthalmol.2014.3518
