You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Disease"].

Please return the output as a JSON object of the format: {"Disease" : ["COVID-19", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Kniest dysplasia: Dr. W. Kniest, his patient, the molecular defect. Kniest dysplasia is a severe chondrodysplasia caused by the defective formation of type II collagen. We report about Dr. Kniest, who first described the condition in 1952, and his patient, who, at the age of 50 years is severely handicapped with short stature, restricted joint mobility, and blindness but is mentally alert and leads an active life. Molecular analysis of the patients DNA showed a single base (G) deletion involving the GT dinucleotide at the start of intron 18 destroying a splice site of the COL2A1 gene. This is in accordance with molecular findings in other patients with Kniest dysplasia and confirms, in the original patient, that the disorder is caused by small inframe deletions often due to exon skipping as a result of COL2A1 splice site mutations..
{"Disease": ["restricted joint mobility", "blindness", "chondrodysplasia", "defective formation of type II collagen", "Kniest dysplasia", "severely handicapped", "short stature"]}