Utility of fluorescence in situ hybridization in pancreatic ductal adenocarcinoma.

Often the diagnosis of pancreas cancer needs to be established from limited cytology specimens or small biopsies. Most ductal adenocarcinomas are histologically well to moderately differentiated and mimicked closely by pancreatitis, and therefore the microscopic diagnosis can be difficult. In addition, there appears to be significant heterogeneity in the outcome of the patients with pancreatic cancer, which cannot be predicted accurately by current prognosticators such as the grade and stage of the tumor.

Cytogenetic aberrations and DNA ploidy in soft tissue sarcoma. A Southwest Oncology Group Study.

We performed cytogenetic analysis and determined DNA content by flow cytometry (FCM) on freshly disaggregated tumor biopsies from 45 patients with soft tissue sarcomas (STS). Cytogenetically aberrant clones characterized 30 (67%) tumors, with the remaining 15 yielding normal karyotypes with or without nonclonal aberrations. No tumors with multiple unrelated clones were observed.

BCR/ABL fusion located on chromosome 9 in chronic myeloid leukemia with a masked Ph chromosome.

A reciprocal translocation, t(10;22)(q22;q11), resulting in a masked Ph chromosome was identified in a patient diagnosed with chronic myeloid leukemia (CML). Both homologs of chromosome 9 were of the normal pattern. Two signals for the ABL probe, both of them hybridized to chromosome 9, were demonstrated via fluorescence in situ hybridization (FISH).

A haploid expressed gene cluster exists as a single chromatin domain in human sperm.

Mammalian spermiogenesis is marked by the initial disruption of the nuclear-histone-DNA complex by the transition proteins for ultimate replacement with protamines. The genes for three of these low molecular weight basic nuclear proteins exist as a single linear array of PRM1, PRM2, and TNP2 on human chromosome 16p13.2.

Viable pregnancies after diagnosis of trisomy 16 by CVS: lethal aneuploidy compartmentalized to the trophoblast.

Increasing utilization of chorionic villus sampling (CVS) has lead to the discovery that the placenta can karyotypically be a very heterogeneous organ, and chromosomal mosaicism within the placental can confuse cytogenetic interpretation. Recently, confined placental mosaicism (confined regions of aneuploidy in the otherwise normal diploid placental and fetus) has been described involving a number of chromosomal abnormalities. Fetal trisomy 16 is considered uniformly lethal early in gestation.