Luke G
Genetics Project – Nyctalopia “Night blindness”
5/6/05

Night blindness and day blindness is a symptom of gene degeneration. There is both an X-linked form and autosomal form. The x-linked version is far more common. Complete night blindness can be caused by a mutation of the NYX gene (300278). This mutation causes a small leucine-rich protein called nyctalopin.
Nyctalopin consists of 481 amino acids. Actually, a family of small leucine-rich protoglycans (LRPs) is produced by the NYX codon. The function of the nyctalopin is only one known so far and that is night blindness in organisms. The specific sequence of nyctalopin is as follows:

1 mkgrgmlvll lhavvlglps awavgacara cpaacacstv ergcsvrcdr agllrvpael
61 pceavsidld rnglrflger afgtlpslrr lslrhnnlsf itpgafkglp rlaelrlahn
121 gdlrylhart faalsrlrrl dlaacrlfsv perllaelpa lrelaafdnl frrvpgalrg
181 lanlthahle rgrieavass slqglrrlrs lslqanrvra vhagafgdcg vlehlllndn
241 llaelpadaf rglrrlrtln lggnaldrva rawfadlael ellyldrnsi afveegafqn
301 lsgllalhln gnrltvlawv afqpgfflgr lflfrnpwcc dcrlewlrdw megsgrvtdv
361 pcaspgsvag ldlsqvtfgr ssdglcvdpe elnlttsspg pspepaattv srfssllskl
421 laprvpveea anttgglana slsdslssrg vggagrqpwf llascllpsv aqhvvfglqm
481 d


Abbreviated (CSNB), Congenital Stationary Night Blindness is actually a group of stable retinal disorders with subtypes and different gene actions. Only one function of this protein is night-blindness in organisms. If we think of nyctalopin as the product of NYX and a small unique member of the LRP protein group, we can say the introns and extrons are very similar between nyctalopin and LRP, which has the same basic sequence.
The expression of the gene is found in the kidney and retina only. In the retina it appears expressed in the photoreceptors, bipolar interneurons, and ganglion cells. Studies done around the year 2000 by Bech-Hanson and Pusch indicate that there are 14 different mutations. Animal model testing done by Gregg in 2003 determine that the phenotype is caused by a 85 base pair deletion in the mouse. Further testing showed that these mice had significant decrease in visual sensitivity. By far more is known now about the x-linked version of night blindness due to this method of testing. Thus, in conclusion, the mouse was a model for human CSNB1 and has been ever since. So far this disease is untreatable as is normal blindness. It is a disability not a lot of people are aware of or have, but we know where it comes from, mutations in the NYX gene, causing the protein nyctalopin to be produced.


thanks for reading the most retarded post ever