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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Muscle most commonly affected by congenital absence is?
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The correct answer is  Pectoralis major and minor muscles are the most common congenitally absent muscles in humans. Ref: Ultrasound of the Musculoskeletal System, 2007, Pages 51, 285; Principles of Neurology By Allan H. Ropper, Raymond Delacy Adams, Maurice Victor, Robe H. Brown, Page 1245; Clinical Pediatric Urology By A. Barry Belman, Lowell R. King, Stephen Alan Kramer, Page 947