Detection of point mutations in human genes by the solid-phase minisequencing method.

The increased understanding of the molecular defects causing human genetic diseases has created a need for diagnostic methods to detect these defects at the DNA level. We have developed a new method, denoted solid-phase minisequencing, for the detection of previously known point mutations. Because of its convenient format, the method is well suited for routine use in the clinical laboratory. We have applied it for diagnosis and identification of carriers of the recessively inherited disease aspartylglucosaminura, for diagnosis of dominantly inherited amyloidosis of the Finnish type and for detecting polymorphic nucleotides of the genome. The solid-phase minisequencing method allows accurate and sensitive quantitation of two sequences which differ from each other by one nucleotide and are present as a mixture in a sample. This feature of the method is an advantage in the diagnosis of mitochondrial disorders caused by heteroplasmic point mutations and for the detection of minimal residual cells carrying somatic point mutations in samples from patients with myeloid malignancies.