Molecular-genetic data characterizations of SLSMD in muscle of 17 patients. Colour of bars correspond with phenotypic group, thickness of the bars corresponds with heteroplasmy level. The exact lengths and heteroplasmy levels were as follows: P6—6193 bp, 72%; P7—4616 bp, 66%, P8—6457 bb, 58%; P9—1835 bp, 59%; P10—2184 bp, 57%; P11—2298 bp, 91%; P12—4961 bp, 78.5%; P13—6302 bp, 68%; P14—2298 bp, 56%; P15—4978 bp, 46%; P16—4963 bp, 76%; P17—7535 bp, 39%; P18—4963 bp, 64%; P19—4963 bp, 46%; P20—3387 bp, 60%; P21—4963 bp, 71%; P22—5395 bp, 30%. For clarity, the 4.977 kb mtDNA deletion (e.g., common deletion) is included at heteroplasmy 100% (grey).