Upsala journal of medical sciences. Supplement最新文献

The fragile-X mental retardation syndrome (FRAX-MR) is one of the most prevalent X-linked diseases. In affected males and in a proportion of carrier females a fragile site at Xq27.3 [fra (X)] is detected when the lymphocytes are cultured under conditions of thymidine deprivation. The fra (X) analysis can be used in the diagnosis of only 56% of carrier females (13, 14) and prenatal diagnosis by this method is not always feasible, thus making genetic counselling of affected families difficult, and sometimes impossible. We have analysed FRAX-MR families using RFLP and four DNA probes from Xq27-Xq28. Estimation of the recombination fraction indicates that the proximal probe F9 is not significantly linked to the FRAX-MR locus while the three distal probes F8, DXS52 and DXS15 show linkage. These probes could be used in the diagnosis of FRAX-MR in those families that do not show evidence for recombination. Used in conjunction with the fra (X) analysis, the segregation studies with these probes should improve the genetic counselling of the FRAX-MR syndrome and should be useful for the genetic and molecular analysis of this unique disease.

There has been strong progress in the field of prenatal prevention during the last decade. New technical advances have made it possible to diagnose new disorders prenatally and in the near future intrauterine treatment will become feasible for some of them.

A total of 80 subjects, 47 of them men and 33 women, with an average age of 25 and an average IQ of 53, were studied using a wide range of psychological methods from 1966 to 1971. In addition data from the subjects' childhood was collected, including IQ, achievement at elementary school and certain social variables. Thirteen years later a follow-up study was carried out. All eighty subjects were traced and the attained social adjustment was analysed from a broad angle, combining quantitative and qualitative methods in the collection of data. In a proceeding longitudinal analysis the intention is to identify, describe and explain fundamental courses or processes of development, focusing both continuity and change over time. The results show that prediction is comparatively feasible as regards cognitive abilities and especially verbal and numerical skills, but considerably more difficult when it comes to more complex abilities. As regards changes and their causes only preliminary results are reported.

The occurrence and aetiology of mild mental retardation (IQ 50-70) and borderline retardation (IQ 71-85) were studied on the basis of a one-year (1966) birth cohort of 12,058 live-born infants, which were followed prospectively up to the age of 14 years. The cumulative incidences for MMR and borderline retardation were 5.5 and 13.4 per 1,000 respectively. In the borderline group there was a male preponderance of 2.3:1 as compared to 1.2:1 in MMR children. A causal factor could be identified for 46.9% of MMR children and 31.4% of borderline ones. Prenatal factors had very little bearing, since only 6% of the MMR and 6.7% of the borderline cases had such, as compared to 28.7% and 20.4% for perinatal factors and 12.1% and 4.3% for postnatal factors. An analysis of the impact of specific obstetrical and perinatal factors revealed that very few constituted relevant relative risks for mental retardation.

Based upon the nationwide Danish registration, all cases with ICD 8 diagnoses 310 and 311 were drawn; 71% lived outside institutions. 7,134 persons were studied for the period 1 January 1976-3 March 1984 and examined in the central register for death, emigration, etc. 5.86%, 446 died during the observation period from 1 January 1976 to 31 March 1984. Mortality tables show estimated survival probability at the end of the 5-year intervals and the life expectancy at the start of the age intervals. Only small differences were found when comparing differences of mortality for sex and residence (institutions or outside institutions). By a linkage study with the Danish Central Register for causes of death in the National Health Service of Denmark, the causes of death were obtained. For males of the age 15-64 an excess mortality of malignant neoplasms, of diseases of the respiratory system, of congenital malformations, and of accidents were found. For females the pattern was less significant.