Abstract: A method for detecting the homozygous or heterozygous state of mutations assumed to be present in a nucleic acid by simultaneously using two primer pairs. The two different primer pairs lead to the production of amplified fragments of different sizes, and the number and quality of the amplified bands enables homozygous and heterozygous items to be distinguished on the basis of said mutation.

Abstract: Disclosed herein is a substantially pure nucleic acid sequence encoding a mammalian 43 kDa non-dystrophin component (.beta.-sarcoglycan) of the dystrophin-glycoprotein complex. Also disclosed are immunogenic peptides which, when used to immunize a mammal, stimulate the production of antibodies which bind specifically to the .beta.-sarcoglycan. Mutations in the .beta.-sarcoglycan gene which are associated with autosomal recessive limb-girdle muscular dystrophy are also disclosed. The identification of such mutations enables the design of nucleic acid probes which hybridize specifically to a mutant form of .beta.-sarcoglycan, or the complement thereof, but not to the DNA of the wild-type form of the gene (or the complement thereof), under stringent hybridization conditions. Such probes are useful, for example, in connection with the diagnosis of autosomal recessive limb-girdle muscular dystrophy.