A new genetic variant of the spinal muscular atrophies in infancy.

The Gene Frequency of Acute Werdnig-Hoffmann Disease (SMA Type 1). A Total Population Survey in North-East England

“…Naturally by the nature of the present study it is impossible to tell whether this is so, but the author thinks that this is the least likely of the three possibilities. This high estimate of the gene frequency of this disease differs from the findings of Zellweger, Hanhart, and Schneider (1972) who have felt that the gene frequency is not higher than that of other autosomal recessive conditions, at least in Switzerland.…”

Unusual pedigree patterns in seven families with spinal muscular atrophy; further evidence for the allelic model hypothesis

“…Furthermore, in pedigrees B-G different types of SMA are present in each pedigree. A few well-documented pedigrees with clinical data, electromyographic and histopathological investigations like our seven pedigrees have been described by Brandt (1950), Amick et al (1966), Almog & Tal (1968), Zellweger et al (1969, 1972), and Zeiler et al (1976, but only Amick et al…”

“…However, several authors have described familial SMA affecting distant relatives, indicating a hereditary pattern incompatible with simple autosomal recessive inheritance (Brandt 1950, Wohlfart et a]. 1955, Kugelberg & Welander 1956, Becker 1964, Amick et al 1966, Almog & Tal 1968, Zellweger et al 1969, White & Blaw 1971, Zellweger et al 1972, Hausmanowa-Petrusewicz et al 1976, Zeiler et al 1976, Zerres & Grimm 1983. Becker (1964) analysed this mode of inheritance and postulated an allelic model.…”

Hereditary distal spinal muscular atrophy with vocal cord paralysis.

“…This 57 year old man dates the onset of his illness to age 14 when she began to walk on her toes. This is the only member of the family where lower limb involvement preceded that in the upper limbs, which appeared ten years later.…”