Genetic Diagnosis of Muscular Dystrophy

1988 Fiscal Year Final Research Report Summary

• Project/Area Number: 61570260
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Hygiene
• Research Institution: Dept. of Hygiene, Miyazaki Medical College.
• Principal Investigator: FUKAMACHI Seijiro Dept. of Hygiene, Miyazaki Medical College. Instructor., 医学部, 助手 (90117458)
• Co-Investigator(Kenkyū-buntansha): TAKENAKA Hitoshi Dept. of Hygiene, Miyazaki Medical College. Instructor, 医学部, 助手 (10179658) ; YAMAGUCHI Tadatoshi Dept. of Hygiene, Miyazaki Medical College. Associate Professor, 医学部, 助教授 (80037598) ; HAMADA Minoru Dept. of Hygiene, Miyazaki Medical College. Professor, 医学部, 教授 (90039529)
• Project Period (FY): 1986 – 1988
• Keywords: Duchenne muscular dystrophy / Genetic disease / genetic diagnosis / サザンブロット・ハイブリッド法

Research Abstract

Southern blot hybridization analysis was carried out for 9 Duchenne muscular dystrophy (DMD) patients DNAs and normal controls as well using genomic probes,pERT87 series probes isolated from a DMD locus. There was not specific restriction fragment length polymor-phism for DMD.One out 9 patients' DNAs were not hybridized to these probes. This showed that a gene locus of these probes was missing in this patient. The rest of 8 patients' DNAs was hybridized. These DNAs were further studied with pulsed field gel electrophore sis(PFG) after Sfil digestion.The DNAs were hybridized at a location of around 280kb (kilobase pairs),which was similar to normal control. The deletion in a sfil fragment hybridizing to pERT87s was not clearly demonstrated.
Linked haplotype analysis of DMD wascarried out in a family with one patient. The patient has already died and the haplotype linked to thedisease was not determined. The mother of the patient had two haplotypes. One was from her father. The other was the same with cousins (not affected withDMD) of the patient. The sister of the patient had two haplotypes. One was from her father. The other was the same with the cousins. The mother and the sister are not probably carriers of DMD.
The diagnosis is definite when the gene deletion can be clearly shown. For PFG, the dia-gnosis is possible when the gene is missing in a large region, but it is difficult when the deletion is in a short region less than 10-20kb. Linked haplotype analysis is possi-ble when haplotype linked to the disease is avalable for family study. The possibility of spontaneous mutations and chromosomal recombinations must always be taken into consi-deration. These limitations are probably due to a large size of DMD gene with more than 2,000kb and a high incidence of the disease with around 10^<-4>. The diagnosis, accurate, easy and fast, is very important for the prevention of DMD onset.