Genomic coordinate 8:86,574,179
Oliver Sacks, “The Island of the Colorblind”, 1997 was the topic of an earlier blog post
Here I present: “Pingelapese Achromatopsia”, Victor McKusick, Mendelian Inheritance in Man’, 1966. 平蓋拉塞無色症。icd10=H53.51
INTRODUCTION.
In the two-hundred fifty (250) Pingelapese people of the eastern Caroline Islands in the Pacific Ocean, a severe ocular abnormality manifested by horizontal pendular nystagmus, photophobia, amaurosis, colorblindness, and gradually developing cataract. About 10% of Pingelapese people are blind from infancy. Segregation analysis and equal sex distribution supported recessive inheritance. The high gene frequency was attributed to reduction in the population to about 9 surviving males by a typhoon (about 1780), combined with subsequent isolation. Whether the disorder is a form of congenital achromatopsia or a tapetoretinal degeneration with primary involvement of the cones was not clear. The impression of tapetoretinal degeneration was based, they thought, on severe myopia which was found in a majority of the affected persons. The disorder is nonprogressive. Pingelapese blindness is distinct from total colorblindness, mainly because of the consistent concurrence of severe myopia in the Pingelapese disease. Refraction is usually normal in total colorblindness.
There is evidence that the form of recessive achromatopsia present in high incidence among Pingelapese islanders is caused by homozygous or compound heterozygous mutation in the cone cyclic nucleotide-gated cation channel (CNGB3) on cytogenetic location 8q21.3 and genomic coordinates 8:86,574,179-86,743,634. The screenshot of the CNGB3 gene 169,456 bp (base pairs) of DNA sequence length is shown BELOW. Nine (9) other genes besides CNGB3 genes in the 8q21.3 cytogenetic location are listed BENEATH.
| Coordinate | Symbol | Genomic Name |
| 8:86,214,063 | SLC7A13 | Solute carrier family 7, member 13 |
| 8:86,342,547 | WWP1 | WW domain-containing protein 1 |
| 8:86,468,266 | RMDN1 | Regulator of microtubule dynamics 1 |
| 8:86,514,435 | CPNE3 | Copine III |
| 8:86,574,179 | CNGB3 | Cyclic nucleotide-gated channel, beta-3 |
| 8:87,870,747 | DCAF4L2 | DDB1- and CUL4-associated factor 4-like 2 |
| 8:88,032,011 | MMP16 | Matrix metalloproteinase 16 |
| 8:89,757,816 | RIPK2 | Receptor-interacting serine/threonine kinase 2 |
| 8:89,901,868 | OSGIN2 | Oxidative stress-induced growth inhibitor 2 |
| 8:89,933,331 | NBN | Nibrin |
