Myelination disturbance in a patient with hyperuricemia and hyperserotoninemia combined with 18q deletion syndrome.

We previously reported a male patient with an 18q21.3 deletion, hyperuricemia and typical symptoms of the Lesch-Nyhan syndrome who lacked hypoxanthine-guanine-phosphoribosyl-transferase (HGPRT) deficiency. The patient developed progressive peripheral neuropathy in additon to his profound mental retardation and self-injurious behavior.

Partial deletion of short arm of chromosome 8.

46, XY, del(8) (p21-pter) aberration was found in a 5 year old boy with moderate craniofacial dysmorphia, mental and somatic retardation. The cytogenetic and clinical features of the patient were compared to 11 cases found in the literature. Partial 8p monosomy does not produce a unique phenotypic alteration.

Partial deletion of short arm of chromosome 18.

Three cases of partial deletion of the short arm of chromosome 18 (pll-pter) are presented. The cytogenetic and clinical features of the patients observed are compared to cases found in the literature. 18p-aberration produces a fairly unique phenotypic alteration, but on the sole basis of the clinical manifestation, without cytogenetic analysis, correct diagnosis cannot be established.

Cytogenetic investigations in 418 couples with recurrent fetal wastage.

418 couples karyotyped because of recurrent miscarriages are reported. 4,78% showed chromosome aberrations (centric fusion, translocation, inversion, mosaicism or fragility of certain chromosome) and 7,19% had normal variants (inv(9), inv(1), 1qh+, 9qh+, etc.).

Unusual chromosome aberrations in 3 children with Down syndrome.

In 3 children with Down syndrome extremely rare chromosome aberrations were found. In the first patient, the karyotype showed 46 chromosomes with a de novo duplication of the q22-qter segment. This finding supports that the 21q22-qter band was responsible for the characteristic mongoloid features.

[Cytogenetic investigations in 817 dysmorphic babies].

By means of G-, C-, and Q-banding techniques 817 dysmorphic children under 1 year of age were cytogenetically investigated. 184 cases of Down's syndrome, 54 cases of various numerical or structural autosomal aberrations, and 29 cases of gonosomal aberration were discovered. The criteria of dysmorphia are the following: intra-, and/or extrauterine retardation, occurrence of minor and/or major malformations, dysfunction of the central nervous system, and the ambiguity of the external genitals, respectively.

Evaluation of information-guidance genetic counselling.

The impact of information-guidance type of genetic counseling was evaluated for the family planning of 2082 consultands. The understanding of the risks, parental decision, and the number of induced and spontaneous abortions were evaluated by the use of questionnaires. The stillbirths, livebirths, infant deaths, and babies with inherited or congenital anomalies were checked by experts.

Hyperuricaemia associated with 18q deletion. Atypical Lesch-Nyhan syndrome?

The existence of a clinically typical Lesch-Nyhan syndrome was observed in a male infant with 18q deletion syndrome. Indirect hypoxanthine-guanine-phosphoribosyl transferase activity determination demonstrated a normal value, and thus the possibility of Lesch-Nyhan syndrome linked to the X-chromosome may be excluded. It is assumed that the uric acid metabolism must be under the primary or secondary effect of one or other of the gene loci on the long arm of chromosome 18, since the existence off a hyperuricaemic syndrome was observed in this 18q deletion patient.

A collaborative study of the aetiology of Turner syndrome.

Data on Turner Syndrome from four sources were analysed for possible associations with several aetiological factors. Two classes of liveborn propositae were included, those with a non-mosaic 45, X karyotype (XO) and those with an isochromosome of the long arm of the X (iso-X). The numbers were 288 and 84 respectively and constitute the largest series of such cases to be analysed to date.

Cases of a Genetic Counselling Clinic.

The 1973--1978 material of the Genetic Counselling Clinic, National Institute of Hygiene in Budapest 1973--1978 consists of 3778 counselees. Based on the disorders of probands, 15 nosological categories are differentiated. The theoretical expectations based on the occurrence of monolocal, chromosomal and multifactorial disorders were compared with the observed experience.