Hi Chirag,
With 427 marks in NEET, you may have a average chance of getting into medical colleges of Karnataka through Karnataka state counselling. Since, you belong to ST category, you still have chance of getting a seat as cutoffs of last year for St category was in the range 360-500.
You can get a list of colleges you have a chance in, using the following college predictor tool: https://medicine.careers360.com/neet-college-predictor?icn=qna&ici=qna_answer
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