ApoE polymorphisms in narcolepsy.

BACKGROUND: Narcolepsy is a common neuropsychiatric disorder characterized by increased daytime sleepiness, cataplexy and hypnagogic hallucinations. Deficiency of the hypocretin neurotransmitter system was shown to be involved in the pathogenesis of narcolepsy in animals and men. There are several hints that neurodegeneration of hypocretin producing neurons in the hypothalamus is the pathological correlate of narcolepsy. The ApoE4 allele is a major contributing factor to early-onset neuronal degeneration in Alzheimer disease and other neurodegenerative diseases as well. METHODS: To clarify whether the ApoE4 phenotype predisposes to narcolepsy or associates with an earlier disease onset, we have genotyped the ApoE gene in 103 patients with narcolepsy and 101 healthy controls. RESULTS: The frequency of the E4 allele of the ApoE gene was 11% in the patient and 15% in the control groups. Furthermore, the mean age of onset did not differ between the ApoE4+ and ApoE4- patient groups. CONCLUSION: Our results exclude the ApoE4 allele as a major risk factor for narcolepsy.

Alpha-sarcoglycanopathy previously misdiagnosed as Duchenne muscular dystrophy: implications for current diagnostics and patient care.

Differential diagnosis of limb-girdle muscular dystrophy, including alpha-sarcoglycanopathy and Duchenne muscular dystrophy, is impossible to acheive on clinical grounds alone; therefore immunohistology, Western blotting and molecular genetic analysis are manadatory for a correct diagnosis. The patient's genotype with a hitherto unknown mutation (Tyr134STOP) in exon 5 adds to the growing spectrum of mutations in the alpha-sarcoglycan gene.

Partial 1p monosomy in a physically and mentally retarded boy.

An 8-year-old boy is reported with marked mental and physical retardation, microcephaly, hypertelorism, mongoloid palpebral fissures, hypoplasia of the maxillary portion of the face, and other discrete anomalies. Deletion of the distal portion of the short arm of the chromosome 1 and the karyotype 46,XY, del(1)(p33----pter) was detected.

[In families of ovarian cancer patients, breast cancer in females and colorectal cancers in males are overrepresented]. / In den Familien von Ovarialkarzinom-patientinnen sind Mamma-karzinome bei Frauen und kolorektale Karzinome bei Männern übervertreten.

A detailed tumour-related family history was obtained from 30 women with histologically verified epithelial ovarian carcinomas. 46% of the anamnestic tumour diagnoses were also verified by obtaining copies of histology reports. Breast cancer was overrepresented among the female relatives and colorectal cancer among the male relatives. This study demonstrates that persons at high cancer risk as well as tumour-prone families of interest for aetiological cancer research can be identified by the simple method of obtaining a family history.

Variable expressivity of hypertelorism in three siblings with Greig syndrome.

Two sisters and one brother are reported with a complex of congenital malformations, hypertelorism, mental retardation, flattened nasal root, divergent strabism++, mongoloid palpebral fissures, malformations of the ears, pathologic alterations of the eye-fundus in terms of optic nerve atrophy, all suggesting Greig syndrome. The major symptom of this syndrome, the hypertelorism, varied considerably in its expressivity in the three siblings. This fact is normally taken into consideration in the diagnosis of Greig syndrome, but we suggest that an alteration in skull formation should be the criterion for the syndrome rather than extreme hypertelorism.

[Familial cancer. Initial results of an inquiry into its occurrence in Basel]. / Familiäre Tumorkrankheiten. Erste Ergebnisse einer Erhebung über ihr Vorkommen in Basel.

The initial results of a systematic study conducted in Basel on the existence of relatives with cancer in the families of more than 600 tumour patients indicate that neoplasm of all organs have forms in whose etiology genetic predisposition is an important factor. This is illustrated by the examples of mammary carcinoma, colorectal carcinoma, gastric carcinoma and lymphoproliferative diseases. Research into genetic predisposition to cancer is of practical value in order to protect persons at risk from the serious consequences of malignant tumors, and also of scientific interest because the characterisation of certain tumours can provide a fundamental insight into the pathogenesis of these diseases.

Mohr syndrome in two siblings.

The present study reports on two siblings of different sex, affected with a condition corresponding to Mohr syndrome. Characteristic symptoms such as epicanthic folds, a broad and flattened nasal root, a lobulated and hamartomatous tongue, poly- and syndactyly on both hands and feet, doubling of the big toes with less frequent features such as marked psychosomatic retardation and overall hypotony have been observed. All the cited anomalies have been of importance in the differential diagnosis. Difficulties associated with classification of new syndromes and the importance for practical clinical genetics of distinguishing between them are discussed.

Retinoblastoma and chromosome 13 deletion.

Two cases of association of unilateral and bilateral retinoblastoma, respectively, with interstitial deletions of long arms of chromosome 13 are presented. The clinical pictures of both children corresponded to the moderate extent of the deletions, with both somatic and mental retardation in both children, and mild phenotypic manifestations (hypertelorism, slight epicanthi, mild facial hirsutism, and partial syndactyly in the child with unilateral retinoblastoma). Opinions concerning the association of chromosome 13 deletion with retinoblastoma are discussed.

Population genetic aspects of primary congenital glaucoma. II. Fitness, parental consanguinity, founder effect.

This paper deals with some other population genetic aspects associated with the incidence of a type of primary congenital glaucoma that occurs very frequently in the Gypsy population of Slovakia. In addition to the decreased fertility of affected individuals of Gypsy origin being determined, the relative reproduction fitness and the selection coefficient against this disease were estimated. An increased number of kinship intermarriages in parents of the patients were recorded, namely in the Gypsy group (45.6%). The average inbreeding coefficient for the Gypsy group (F = 0.0091) and the non-Gypsy group (F = 0.0030) was calculated. Based on the high frequency of primary congenital glaucoma in a relatively small Gypsy subpopulation and on data about their origin, immigration, and settlements in the territory of Slovakia, the authors consider a special case of gene drift--the founder effect--to be the most plausible explanation of the given fact.

Population genetical aspects of primary congenital glaucoma. I. Incidence, prevalence, gene frequency, and age of onset.

This paper presents some characteristics of the population genetics of primary congenital glaucoma in Slovakia. The overall incidence in Slovakia is 1:10,500, while being 1:1,250 in the Gypsy subpopulation of Slovakia and 1:22,000 in the non-Gypsy population. For a special type of congenital primary glaucoma, transmitted by autosomal recessive inheritance in Gypsies the gene frequency may be estimated to reach 2.8%. Early onset of the disease enabling diagnosis soon after birth in 82% of patients may be considered another characteristic of this type of primary congenital glaucoma.

Familial occurrence of partial trisomy 4q and probable monosomy 5p due to 4q/5p translocation.

Translocation between chromosomes 4q and 5p has been observed in 12 members of a family. Multiple deaths occurred in early childhood in the family but spontaneous stillbirth did not show an increased frequency. In two children, identical cytogenetic findings were found consisting of translocation between 4q and 5p, resulting in trisomy 4(q31 leads to qter) and, based on clinical symptomatology, of a probably monosomy 5(p15 leads to pter). The clinical picture of both children included the main features of the cri du chat syndrome: a low birthweight, catlike cry, severe psychomotor retardation, hypotonicity, antimongoloid slant of the eyelids, microcephaly together with other symptoms determined by trisomy 4q.