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: ["Variant", "Disease", "Species", "CellLine", "Chemical", "Gene"].

Please return the output as a JSON object of the format: {"CellLine": ["hRPTEC", ...], "Chemical": ["Glucose", ...], "Disease": ["Diabetes", ...], "Gene": ["HNF-6", ...], "Species": ["Patients", ...], "Variant": ["Pro75Ala", ...]}. 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:

Coincidence of mutations in different connexin genes in Hungarian patients. Mutations in the GJB2 gene are the most common cause of hereditary prelingual sensorineural hearing impairment in Europe. Several studies indicate that different members of the connexin protein family interact to form gap junctions in the inner ear. Mutations in different connexin genes may accumulate and, consequently lead to hearing impairment. Therefore, we screened 47 Hungarian GJB2- heterozygous (one mutation in coding exon of the GJB2 gene) patients with hearing impairment for DNA changes in two further connexin genes (GJB6 and GJB3) and in the 5' non-coding region of GJB2 including the splice sites. Eleven out of 47 GJB2-heterozygous patients analyzed carried the splice site mutation -3170G>A in the 5'UTR region of GJB2. One out of these 11 patients showed homozygous -3170G>A genotype in combination with p.R127H. Next to the GJB2 mutations we noted 2 cases of deletion in GJB6 [Delta(GJB6-D13S1830)] and 3 (2 new and 1 described) base substitutions in GJB3 [c.357C>T, c.798C>T and c.94C>T (p.R32W)] which are unlikely disease-causing. Our results suggest the importance of routine screening for the rather frequent -3170G>A mutation (in addition to c.35delG) in patients with hearing impairment.
{"CellLine": [], "Chemical": [], "Disease": ["hearing impairment", "sensorineural hearing impairment"], "Gene": ["GJB2", "GJB3", "GJB6"], "Species": ["patients"], "Variant": ["c.35delG", "c.357C\u003eT", "p.R127H", "c.94C\u003eT", "c.798C\u003eT", "-3170G\u003eA", "p.R32W"]}