Inheritance of idiopathic torsion dystonia among Jews.

Abstract

Idiopathic torsion dystonia (ITD) has long been considered to be genetically determined, but the pattern of inheritance has been unclear. It has been suggested that inheritance may differ in Jews and non-Jews. In the present study, data gathered in a nationwide survey of ITD in Israel were analysed. Between 1969 and 1980, 47 patients were collected, of whom 40 were of European origin. In these European Jews, the ITD frequency was about 1:23 000 live births, which was five-fold greater than in Jews of Afro-Asian origin. Assuming that all cases fit the same genetic model, an X linked or a simple autosomal recessive model of inheritance did not agree well with our data. An autosomal dominant model with low penetrance could have accounted for our observations and would yield an ITD gene frequency in European Jews of 3 to 4: 100 000. In view of the increased ages of their fathers, the isolated cases may have included some new mutations. Multifactorial inheritance was also possible. However, it may be inappropriate to assume that all cases have the same genetic basis, or even that all are inherited.

Natural Course of Idiopathic Torsion Dystonia among Jews

“…A previous study of the inheritance of ITD in Israel [1] included 46 Jewish patients. In the present study, 5 o f those cases were excluded because o f insufficient data on the natural history of the disease; 2 were excluded after further neurological examination revealed mani festations inconsistent with the criteria mentioned above.…”

“…The method used to ascertain cases nationwide has been described in previous papers [1,8,9]. The five diagnostic criteria necessary for inclusion in this co hort were: (1) dystonic posturing or dystonic move ment, (2) a progression o f the abnormality during the course o f the illness, (3) no history o f perinatal abnor malities such as asphyxia or jaundice and no history of encephalitis or brain trauma, (4) no other abnormal neurological signs (cognitive, sensory, pyramidal or cerebellar), and (5) no metabolic disorder (e.g., Wil son's disease, gangliosidosis or abnormal calcium lev els) that could account for the condition.…”

“…Idiopathic torsion dystonia (ITD) is a dis ease which is thought to be transmitted geneti cally by a single dominant gene [1][2][3]. Like many other diseases with a similar mode of inheritance, ITD has a wide clinical spectrum: patients differ in age of onset, rate of progres sion, and extent of involvement of body parts, as well as in degree of disability.…”

Israeli National Neurological Disease Register

“…In these European Jews, the ITD frequency is about 1 per 23,000 live births, which is 5-fold greater than the frequency among Jews of Afro-Asian origin [16,17], There were four families, all of European origin, with more than one affected individual; these families accounted for 14 cases of ITD. Assuming that all cases fit the same genetic model, predic tions based on an X-linked and a simple autosomal recessive mode of inheritance do not agree with our observation of frequency.…”

The dystonias.

“…There is no reason to doubt the sincerity and truth of Mr Clarke's statement on 10 July 1989 that "The comprehensive and high quality health service which will be needed to face the demands and challenges of tomorrow's world will depend crucially on the standard of medical education we provide and the range and quality of the nation's medical research programmes. Both are an intrinsic part of our commitment to the NHS" (speech to doctors in London).…”