Symptom Information: Sort according to HPO 

	Symptom Information	Symptom	Abundance	Frequency	Pubmed	Source	DB Freq
1	(HPO:0000654)	Decreased light- and dark-adapted electroretinogram amplitude					17 / 7739
2	(HPO:0001123)	Visual field defect					30 / 7739
3	(HPO:0007642)	Congenital stationary night blindness					16 / 7739
4	(HPO:0007737)	Bone spicule pigmentation of the retina					26 / 7739