Aortic distensibility in children with the Marfan syndrome.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to I Kaitila.
Explore the source record for details and available documents.
Biochemical and molecular genetic studies have recently suggested that mutations in the gene coding for fibrillin on chromosome 15 result in Marfan syndrome. To our knowledge, only one mutation in the fibrillin gene has been published. Here we report the results of screening 20 unrelated MFS patients for mutations in fibrillin cDNA by the single-strand conformation polymorphism technique. We found two mutations, both of which appear in the heterozygote form and code for a shortened fibrillin polypeptide. The first mutation is a large in-frame deletion of 366 bases of the fibrillin mRNA, shown to result in a truncated but secreted polypeptide found in the fibroblast culture of the patient. The second mutation is a G-to-A transition resulting in the substitution of a stop codon for a tryptophan codon and thus predicting the premature termination of the polypeptide chain. We screened 60 other, unrelated MFS patients for these mutations as well as for the previously reported mutation (arginine-239 to proline) and found none of the three mutations in any of these patients. These data suggest that most MFS families carry their own distinct mutation.
Cartilage-hair hypoplasia is a metaphyseal chondrodysplasia with short-limbed short stature. In childhood radiographs the metaphyseal regions of the tubular bones are widened, scalloped and irregularly sclerotic. We have analyzed radiological characteristics and skeletal growth in 149 radiographic surveys of 82 Finnish patients. All extremity long bones were affected and short for age. The growth failure was progressive. In the adults the median relative lengths were for the humerus -6.3 SD, radius -8.6 SD, ulna -6.7 SD, femur -9.7 SD, tibia -8.7 SD, and fibula -6.8 SD. the severity of the metaphyseal changes correlated with the degree of the growth failure. The skeletal age was markedly retarded in 14% of the patients. Caudal widening of the interpediculate distance in the lumbar spine was observed in 90% of the patients, but it tended to be less than normal. The sagittal diameter of the spinal canal was normal in the cervical region but decreased in the lumbar region. Mild scoliosis was observed in one-fourth of the patients, and its incidence increased with age. Lumbar lordosis was moderately increased. Thoracic deformity was observed in 82% of the patients. The relative interorbital distance was increased with the median of +2.2 SD in the adults.
Diastrophic dysplasia results in severe disproportionate growth failure, generalized joint dysplasia, and early osteoarthrosis of the hips. A total hip arthroplasty is often necessary in patients afflicted with diastrophic dysplasia by time they reach early middle age. During 1983-1988, total hip arthroplasties were performed on six women and four men (15 hips) with diastrophic dysplasia at the Orthopaedic Hospital of the Invalid Foundation. The mean age of the patients at the time of operation was 37 years and the mean height was 133 cm. A Lord endoprosthesis was used in nine hips and a Biomet endoprosthesis in six. Cementless fixation was used in all cases. Autogenous bone grafting to the acetabulum was performed in six hips. Simultaneous corrective osteotomy of the proximal femur and transposition of the greater trochanter was performed in three cases. Soft tissue release and tenotomies were performed in 10 hips. The average follow-up period was 5 years. Overall clinical results were good, with marked relief of pain and improvement of hip joint mobility. Aseptic loosening of the acetabular component was noted in two hips. As for complications, two femoral nerve paresis and two perioperative fractures of the proximal femur occurred, which all healed.
Linkage disequilibrium mapping in isolated populations provides a powerful tool for fine structure localization of disease genes. Here, Luria and Delbrück's classical methods for analysing bacterial cultures are adapted to the study of human isolated founder populations in order to estimate (i) the recombination fraction between a disease locus and a marker; (ii) the expected degree of allelic homogeneity in a population; and (iii) the mutation rate of marker loci. Using these methods, we report striking linkage disequilibrium for diastrophic dysplasia (DTD) in Finland indicating that the DTD gene should lie within 0.06 centimorgans (or about 60 kilobases) of the CSF1R gene. Predictions about allelic homogeneity in Finland and mutation rates in simple sequence repeats are confirmed by independent observations.
Cartilage-hair hypoplasia is an autosomal recessive osteo-chondrodysplasia which results in short stature, sparse hair and impaired cell-mediated immunity. In a study of 88 Finnish patients we found episodes of anaemia and/or macrocytosis during childhood in 86% of the patients. The reticulocyte index was always low in relation to anaemia. Bone marrow examination revealed decreased erythropoiesis in six of eight anaemic patients studied. Anaemia was most prevalent and severe during infancy. Spontaneous recovery occurred before adulthood in all patients except in three infants with fatal hypoplastic anaemia. Sixty-two percent of the patients had had lymphopenia and 24% neutropenia. Presence of anaemia significantly correlated to severity of immunodeficiency and growth failure and to presence of neutropenia. Disordered erythrogenesis is an integral feature of cartilage-hair hypoplasia and may, together with growth failure and immunodeficiency, reflect a generalized defect in cellular proliferation.
Cartilage-hair hypoplasia is an osteochondrodysplasia with short-limbed short stature. The cartilage-hair hypoplasia gene is exceptionally prevalent in Finland; more than 100 patients have been identified. We have analyzed the growth of 100 Finnish patients and present cartilage-hair hypoplasia-specific growth charts of height and weight for height. The disproportions were analyzed by sitting height, subischial leg height, sitting height:height ratio, and span-height difference. The stature was short at birth with a mean relative length of -3.0 SD. The median adult height was 131.1 cm (-7.9 SD, range 110.7 to 149.0 cm) for 15 males and 122.5 cm (-7.9 SD, range 103.7 to 137.4 cm) for 20 females. The progression of the growth failure was partly explained by weakness or absence of pubertal growth spurt. Weight for height was above normal median in childhood and increased further at puberty. Most of the adults were overweight. The adults' mean relative head circumference was -0.9 SD. Growth was disturbed both in the limbs and in the spine, more severely in the limbs. Adult height showed no correlation with the midparent height. The charts are useful for assessment of growth, prediction of adult height, detection of superimposed disorders, and evaluation of growth-accelerating therapy.
The exceptionally high prevalence of diastrophic dysplasia in Finland has enabled us to analyse the foot deformities of 102 patients at their first orthopaedic evaluation and classify 204 feet into five categories. The most common finding (43%) was a foot with tarsal valgus deformity and metatarsus adductus; 37% showed either equinovarus adductus (29%) or equinus (8%) deformities. At the first examination 13% showed metatarsus adductus deformity alone, and 7% were clinically normal. The expression 'club foot', generally used for the foot deformity in diastrophic dysplasia is a misnomer. There is a wide spectrum of deformities, some of them specific for the condition.
Diastrophic dysplasia (DTD) is an autosomal recessive osteochondrodysplasia. Patients have short-limbed short stature and suffer from generalized joint dysplasia. We have recently mapped DTD to the distal long arm of chromosome 5. Here we report the localization of DTD in relation to 16 polymorphic markers on distal 5q. No recombinations occurred with two loci, D5S72 and D5S66. One presumptive candidate gene, osteonectin (SPARC), could be excluded on the basis of three recombinations with the DTD locus. Multipoint linkage analysis performed against a fixed order of markers placed DTD between glucocorticoid receptor (GRL) and SPARC favored by the odds of 33:1 over the next best location of DTD between D5S72 and D5S55. The sex-averaged distance between the definite flanking markers, GRL and D5S55, is 17.5 cM. From previously reported data on the physical localization of markers, we conclude that the DTD locus is in 5q31-q34.
Diastrophic dysplasia is an autosomal recessive disorder of the skeleton, characterized by disproportionate short stature, generalized joint deformities, club feet, deformed ear pinnae, and, frequently, spinal deformity and cleft palate. Diastrophic dysplasia is more common in Finland than elsewhere. We studied 101 patients with an age range from newborns to 79 years to find out the frequency and type of spinal deformities, the early signs of progressive cases, and to follow the natural history of the disease. In the follow-up study, 17 patients were under 10 years, 21 under 21 years, and 63 over 21 years of age. One-third of the patients had cervical kyphosis; in the most severe case the kyphosis was 180 degrees and led to quadriplegia during anesthesia. In three patients, cervical kyphosis resolved spontaneously before the age of 5 years. The overall frequency of scoliosis was 37%; 49% in women and 22% in men. Only 13 patients had curves greater than 50 degrees; these curves constituted distinct rotation at the apex from the early evolution of the curve. The early signs of severe curves were detectable at the age of 2 to 4 years. Only two patients were operated on because of scoliosis; one with fusion in situ and the other instrumented with the pediatric Cotrel-Dubousset instrumentation. Three patients had a brace, which did not prevent the progression of the curve. Symptoms referring to a narrow spinal canal were registered in four patients, two of which were operated on; a lumbar posterior decompressive procedure was made at adult age.
Explore the source record for details and available documents.
BACKGROUND: Marfan syndrome, "the founding member" of the heritable disorders of connective tissue, is a common autosomal dominant disorder with highly variable clinical manifestations in the skeletal, ocular, and cardiovascular systems. The fundamental defect leading to this disease has escaped definition despite decades of research efforts by several groups of investigators. METHODS AND RESULTS: Using linkage analyses with polymorphic markers of the human genome, we mapped the genetic defect to chromosome 15 in five families with Marfan syndrome. With three polymorphic markers we obtained definitive proof of linkage in these families (lod score = 3.92, theta = 0.0 +/- 0.11). The most probable location of the gene for the disease is currently D15S45 (lod score = 3.32, theta = 0.0 +/- 0.12). CONCLUSIONS: The chromosomal localization of the mutation in Marfan syndrome is a first step toward the isolation and characterization of the defective gene and serves as a diagnostic test in families in which cosegregation of these markers with the disease has been confirmed.
Marfan syndrome represents a heterogeneous connective tissue disease, the symptoms arising in several tissues and organs. The defective gene(s) behind this autosomal dominant condition has not been found despite considerable research. The main targets of the research have been the genes coding for connective tissue components. Several of the candidate genes suspected to be defective in Marfan syndrome are located on the long arm of chromosome 2. These genes include a cluster of two genes coding for fibrillar collagens COL3A1 and COL5A2, and a third member of the collagen gene family: COL6A3. Furthermore, genes for elastin (ELN) and fibronectin (FN) are also located in this area of chromosome 2. We studied this chromosomal area using restriction fragment length polymorphism (RFLP) linkage analysis in five Finnish Marfan families with affected members in three generations. In two point linkage analyses, Lod scores of -3.192 (theta = 0.1) to COL3A1, -1.683 (theta = 0) to COL6A3 and -2.664 (theta = 0.01) to FN were obtained, whereas the linkage analysis between elastin and the disease was non-informative (Lod score 0.444, theta = 0). With the multipoint linkage analysis that permits simultaneous examination of several loci and more efficient use of family data, we obtained an exclusion of all these loci as the site of the mutation leading to Marfan syndrome in these families.
We have used polymorphic DNA markers to map the gene for a clinically well-characterized form of osteochondrodysplasia, diastrophic dysplasia (DD), an autosomal recessive disorder of unknown pathogenesis. Linkage was analyzed in 13 families with two or three affected sibs comprising a total of 84 individuals. Positive two-point logarithm-of-odds (lod) scores were obtained between the DD locus and three polymorphic markers on chromosome 5. The highest pairwise lod score estimate of 7.37 with zero recombination to locus D5S72 suggests very tight linkage. There was no evidence of heterogeneity. Multipoint linkage analysis against the published order of the three loci gave the result centromere-D5S84-(DD, D5S72)-D5S61-terminus with a four-point lod score of 9.11. The present findings place the DD locus distal to the gene for adenomatous polyposis coli on the distal part of the long arm of chromosome 5. Our results provide a basis for refining the map position of the DD locus followed by physical localization, isolation, and characterization of the gene.
A family with craniofrontonasal dysostosis (craniofrontonasal dysplasia) is described. There were three severely affected females, two of them daughters of apparently healthy parents. Examination of the male relatives revealed orbital hypertelorism and other minor anomalies in two of them, including the father of the two affected daughters. This family emphasizes the wide variation in the phenotype of craniofrontonasal dysostosis and suggests that male relatives with minor manifestations of the syndrome may be at high risk of having severely affected daughters. The expression of the gene may be modified by the sex.
Explore the source record for details and available documents.
The involvement of the cartilage specific type II collagen gene (COL2A1) was studied in nine patients with diastrophic dysplasia in the Finnish population, where the prevalence of this chondrodystrophy clearly exceeds that reported for other populations. COL2A1 was chosen as the candidate gene based on previous morphological and chemical studies which suggested abnormal structure of type II collagen in diastrophic dysplasia. Southern analysis of the patients' DNA showed no disease related differences in any of the restriction fragments covering the 30 kb COL2A1 gene. As a second approach, the nine patients and their 74 relatives were studied for the inheritance of the type II collagen gene. Three of the patients with diastrophic dysplasia were not homozygous for the intragenic RFLP markers, which suggests that the disease is not linked to the type II collagen gene. Multipoint linkage analysis gave a lod score of -2.95, which conclusively excluded the COL2A1 gene as the mutation site in diastrophic dysplasia in these families.
During a seven-year period we observed 14 children who had chronic osteomyelitislike disease. The bacterial cultures from the bone lesions were negative. In eight patients the findings were compatible with chronic recurrent multifocal osteomyelitis (CRMO), in four the findings were compatible with chronic sclerosing osteomyelitis of Garré, and two had osteomyelitis of the clavicle. In patients with CRMO, lymphocyte subpopulations, the responses to mitogens, and the chemotactic and chemokinetic responses showed no consistent abnormalities. After a mean follow-up of 4.5 years (range, one to ten years), all four patients with osteomyelitis of Garré were symptomatic, and two had complications. Only two of the eight patients with CRMO had active disease. The course had been complicated by growth disturbances in one patient and by thoracic outlet syndrome in another. Wegener's granulomatosis later developed in a patient with CRMO.