Friedreich's ataxia is the most common inherited ataxia. Ninety‐six percent of patients are homozygous for GAA trinucleotide repeat expansions in the first intron of the frataxin gene. The remaining cases are compound heterozygotes for a GAA expansion and a frataxin point mutation. We report here the identification of 10 novel frataxin point mutations, and the detection of a previously described mutation (G130V) in two additional families. Most truncating mutations were in exon 1. All missense mutations were in the last three exons coding for the mature frataxin protein. The clinical features of 25 patients with identified frataxin point mutations were compared with those of 196 patients homozygous for the GAA expansion. A similar phenotype resulted from truncating mutations and from missense mutations in the carboxy‐terminal half of mature frataxin, suggesting that they cause a comparable loss of function. In contrast, the only two missense mutations located in the amino‐terminal half of mature frataxin (D122Y and G130V) cause an atypical and milder clinical presentation (early‐onset spastic gait with slow disease progression, absence of dysarthria, retained or brisk tendon reflexes, and mild or no cerebellar ataxia), suggesting that they only partially affect frataxin function. The incidence of optic disk pallor was higher in compound heterozygotes than in expansion homozygotes, which might correlate with a very low residual level of normal frataxin produced from the expanded allele. Ann Neurol 1999;45:200–206

We report a retrospective study of diabetic children, 0--14 years of age, from seven Swedish departments of paediatrics. There were 359 new cases in the years 1970--1975. Notification suggested that there was a mean yearly incidence of 19.6 cases per 100 000 with a year to year variation of 10.0--26.4 per 100 000. Consequently about 330 new cases of childhood diabetes would be expected in Sweden every year. Incidence varied considerably between different geographical areas. The age distribution was bimodal with a main peak at about 12 years and another peak at about 7 years. There was some evidence for clustering of new cases in January and the autumn. The mean prevalence of childhood diabetes in the seven districts was 1.3 per 1 000.

Summary The purpose of this study was to investigate the incidence and genetics of metachromatic leuco‐dystrophy (MLD). A series of 13 cases of late infantile MLD and 2 cases of juvenile MLD was collected from the northern part of Sweden and studied together with their relatives. The series was considered to be adequately representative of the true occurrence of MLD during the period 1955–1965. The incidence rate for late infantile MLD was estimated to be about 1 per 40 000. The MLD patients were highly concentrated to the south‐west part of Norrland. From the family analysis it was concluded that late infantile MLD is most probably transmitted by an autosomal recessive gene.

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Two sibs with identical features of short-limbed dwarfism, a normal skull and face and normal intelligence are described. On the basis of the radiological and clinical characteristics the condition must be included within the group of spondylometaphyseal dysplasias. In contrast to the familial cases described up to now in which the mode of inheritance was autosomal dominant, the trait in the two children described here was transmitted as an autosomal recessive.