Congenital cardiovascular malformations associated with chromosome abnormalities: an epidemiologic study.

The Baltimore-Washington Infant Study is a population-based case-control study that seeks to identify risk factors for cardiovascular malformations. Between 1981 and 1986, a total of 2102 infants with cardiovascular malformations were ascertained, among whom 271 (12.9%) also had a chromosome abnormality. Among 2328 random control subjects, only two had a chromosome abnormality. Down syndrome with cardiovascular malformations had a maternal age-adjusted regional prevalence of 4.33/10,000 for the white population and 3.70/10,000 for the nonwhite population. Endocardial cushion defect, the predominant cardiac abnormality in Down syndrome (60.1%), rarely occurred as an isolated cardiac lesion (2.8%). The absence of transpositions and the rarity of heterotaxias and of right- and left-sided obstructive lesions in trisomies indicate that there may be a genetic influence on specific embryologic mechanisms. Alimentary tract lesions were more common in Down syndrome than among euploid patients with heart disease and more severe than in control subjects. Urinary tract lesions also occurred in excess of the rate in control subjects. The coexistence of these major malformations with heart disease raises the possibility of incomplete expression of the VA(C)TER (vertebral, anal, cardiac, tracheal, esophageal renal) association. The selective association of chromosome abnormalities with certain cardiovascular defects is now beginning to be explained by reported embryologic studies on cellular characteristics. An explanation of the negative association with transposition and obstructive lesions requires further multidisciplinary studies on genetic and epigenetic factors.

Chromosome findings and prognosis in 15 patients with neuroblastoma found by VMA mass screening.

We performed chromosome analysis of 15 neuroblastomas found by mass screening using a vanillymandelic acid spot test. We found near triploid chromosome abnormalities, ranging from 60 to 77 chromosomes, in the tumor cells from 14 patients, and hyperdiploidy with the mode of 50 in cells from one. A structural abnormality was observed in only one patient. We did not find a marker chromosome 1, homogeneously staining region, or double minutes, which have been previously reported in advanced neuroblastomas or in cell lines. All of our patients were completely free of disease 4 to 32 months after diagnosis. We consider that patients with hyperdiploidy or near triploidy are different from those with marker chromosome 1, homogeneously staining region, or double minutes and may constitute a subgroup with a good prognosis in childhood neuroblastoma.

The 18p-syndrome and IgA deficiency

Culturas de sangue de uma paciente com retardo de crescimento e infecçäo recorrente mostram cariótipo 46,XX,18p-. As bandas excluiram a presença de translocaçäo ou inversäo pericêntrica e mostram que o cromossomo anormal tem uma deficiência simples. Os dados clínicos säo concordantes com a síndrome 18p- clássica, mas a doente apresenta também megaesófago, uma má formaçäo que näo tem sido descrita previamente. Os estudos imunológicos mostram uma ausência completa de IgA. A associaçäo de 18p- e anormalidade imunológica tem sido observada repetidamente e o significado da mesma é discutido neste trabalho

Trisomía parcial del cromosoma 1.46,XX dir. dup (1q) (q32- q44) / Partial trisomy 1q

Se aporta la observación de un caso de trisomía 1q parcial asociada a manifestaciones fenotípicas y anatomopatológicas propias de la anomalía de Di George. La variable expresión de la misma parece correlacionarse con distintas circunstancias asociadas, que se interpretan como causantes de la mencionada anomalía. Los autores establecen la relación entre cromosomopatía y alteración fenotípica, sugiriendo la obligatoriedad del estudio citogenético de aquellos cuadros que clínicamente correspondan a los distintos grados de síndrome de Di George