PubMed Health⌕ Search

Biomedical subjects

R Tenconi

Publications and source records attributed to R Tenconi.

At least 91 records · Page 5Linked to original sources

Cytogenetic findings in 4952 prenatal diagnoses. An Italian collaborative study.

The development of prenatal diagnosis in Italy was made difficult by the restrictions of the old abortion law and only in recent years has a consistent number of cases been investigated. We report the experience on prenatal chromosome diagnosis of ten Italian centers participating in a collaborative study on 4952 diagnoses performed from 1972 to 1980. The main indication groups were: advanced maternal age (2882 cases), previous child with chromosome anomaly from parents with normal karyotype (847 cases), and chromosome anomaly in one parent (97 cases). The other indications for amniocentesis, including cases without a cytogenetic risk, have been assembled into a "miscellaneous" group (1126 cases). We found 125 abnormal fetal karyotypes (2.5%) of which 89 were unbalanced (1.8%). The frequencies and types of chromosome anomalies are reported in detail for each indication group and are compared with the corresponding one from the European Munich Conference. The great majority of these Italian data were not included in the Munich report.

Chromosome Aberrations↗

The "cat eye syndrome": dicentric small marker chromosome probably derived from a no.22 (tetrasomy 22pter to q11) associated with a characteristic phenotype. Report of 11 patients and delineation of the clinical picture.

Eleven patients with the so-called Cat Eye syndrome are reported including a more detailed description of the original cases reported by Schmid and Fraccaro. All cases had, in addition to a normal karyotype, a small extra G-like chromosome which appeared to be an isochromosome for the juxtacentromeric region (pter to q11) of an acrocentric chromosome. None were mosaics. Clinical findings and further cytogenetic studies in a few cases suggest that these markers probably derive from a No. 22 chromosome. Characteristic features of the Cat Eye syndrome in these 11 patients and those reviewed from the literature are: ocular coloboma which may involve the iris, choroid and/or optic nerve, preauricular skin tags and/or pits which are probably the most consistent feature, congenital heart defect, anal atresia with a fistula, renal malformations such as unilateral absence, unilateral or bilateral hypoplasia, and cystic dysplasia, and antimongoloid position of eyes. Intelligence is usually low-normal, although moderate retardation is also seen. There is great variability in the clinical findings ranging from near normal to lethal malformations. Less frequent, but also characteristic findings are: microphthalmia, microtia with atresia of the external auditory canal, intrahepatic or extrahepatic biliary atresia and malrotation of the gut. Direct transmission of the marker from one generation to the other was observed in both sexes. In those families, there was considerable variability in the clinical findings between affected family members. These cases show that there is a bias of ascertainment for patients who have the more striking malformations, especially those with ocular coloboma and anal atresia, a combination which appears to be present in only a minority of cases. Many mildly affected patients probably remain undetected. It is proposed that the term Cat Eye syndrome should be applied only to cases with trisomy or tetrasomy of not more than 22pter to q11 and without additional duplication or deletion of another autosomal segment.

Adolescent↗

Regional assignment of catalase (CAT) gene to band 11p13. Association with the aniridia-Wilms' tumor-Gonadoblastoma (WAGR) complex.

A gene dosage effect for catalase (CAT) was investigated in three individuals : one with 11p13 deletion, aniridia, ambiguous genitalla, and gonadoblastoma ; one trisomic for 11p with the exception of 11p13; and one trisomic for 11p13. Results were compatible with the assignment of CAT to 11p13 and its linkage with the aniridia-gonadoblastoma or Wilms' tumor complex (WAGR).

Adolescent↗

Syndrome +12p. Case report and review.

Familial 12/15 translocation with a child trisomic for the short arm of chromosome 12 (segment of 12.1 leads to pter) is reported. The clinical picture of the child is strikingly similar to previous reports of 12p trisomy. The main symptoms of 12p syndrome are defined.

Child, Preschool↗

[Localization of the gene of the glyceraldehyde 3 phosphate dehydrogenase on the distal segment of the short arm of the chromosome 12].

The enzymatic activity of G3PD and LDH-B in erythrocytes has been assayed in three patients carrying a rearrangement of the short arm of chromosome 12. The first patient is trisomic for the whole short arm. The second is trisomic only for the distal part and the third is monosomic for the proximal part. G3PD: Activity increased in patients 1 and 2 and normal in patient 3. LDH-B: Activity increased in patients 1 and 2 and decreased in patient 3. From these observations it is concluded that the erythrocytic G3PD locus is localized on the distal part of 12p, between 12p12.2 and 12 pter, and that LDH-B locus is on the middle third between 12p12.1 and 12p12.2

Child, Preschool↗

Trisomy 4q32 leads to 4qter due to a maternal 4/21 translocation.

The case is described of a malformed girl with partial trisomy for a segment of the long arm of chromsome (4q32 leads to qter) due to an unfavourable segregation of a maternal reciprocal translocation t(4;21) (q32q22). The clinical comparison between the child and patients previously described by other authors does not suggest the existence of a syndrome associated with trisomy 4q+.

Adult↗