Molecular combing compared to Southern blot for measuring D4Z4 contractions in FSHD.

We compare molecular combing to Southern blot in the analysis of the facioscapulohumeral muscular dystrophy type 1 locus (FSHD1) on chromosome 4q35-qter (chr 4q) in genomic DNA specimens sent to a clinical laboratory for FSHD testing. A de-identified set of 87 genomic DNA specimens determined by Southern blot as normal (n = 71), abnormal with D4Z4 macrosatellite repeat array contractions (n = 7), indeterminate (n = 6), borderline (n = 2), or mosaic (n = 1) was independently re-analyzed by molecular combing in a blinded fashion. The molecular combing results were identical to the Southern blot results in 75 (86%) of cases.

Spectral Karyotyping for identification of constitutional chromosomal abnormalities at a national reference laboratory.

Spectral karyotyping is a diagnostic tool that allows visualization of chromosomes in different colors using the FISH technology and a spectral imaging system. To assess the value of spectral karyotyping analysis for identifying constitutional supernumerary marker chromosomes or derivative chromosomes at a national reference laboratory, we reviewed the results of 179 consecutive clinical samples (31 prenatal and 148 postnatal) submitted for spectral karyotyping. Over 90% of the cases were requested to identify either small supernumerary marker chromosomes (sSMCs) or chromosomal exchange material detected by G-banded chromosome analysis.

Fluorescence in situ hybridization and K-ras analyses improve diagnostic yield of endoscopic ultrasound-guided fine-needle aspiration of solid pancreatic masses.

Objectives: Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) is the main diagnostic modality for pancreatic mass lesions. However, cytology is often indeterminate, leading to repeat FNAs and delay in care. Here, we evaluate whether combining routine cytology with fluorescence in situ hybridization (FISH) and K-ras/p53 analyses improves diagnostic yield of pancreatic EUS-FNA.

Mosaic tetrasomy 8q: inverted duplication of 8q23.3qter in an analphoid marker.

We observed an analphoid marker chromosome stable through cell division in a 16-year-old girl with developmental delay, short stature, limb contractures, and ovaries containing multiple cysts. She also developed myasthenia gravis at 15 years. The marker chromosome, present in 75% of metaphases (and in 90% of transformed lymphoblastoid cells), was C-band negative, and had no pan alpha-satellite sequences detectable by fluorescence in situ hybridization (FISH).

A FISH study of variant Philadelphia rearrangements.

A total of 39 variant Philadelphia (Ph) translocations were studied by fluorescence in situ hybridization (FISH) using MBCR/ABL, mBCR/ABL, or DBCR/ABL probes. Seven cases did not have a BCR/ABL fusion signal. Of a total of 32 fusion-positive cases, 5 were simple variants involving chromosome 22 and another chromosome apart from chromosome 9; 23 were complex variants involving chromosomes 22, 9, and a third chromosome (18 cases), or 22, 9, and two other chromosomes (4 cases).

De novo mosaic add(3) characterized to be trisomy 14q31-qter using spectral karyotyping and subtelomeric probes.

We describe a 19-year-old patient with a de novo mosaic add(3) chromosome (extra material of unknown origin on the 3q). The use of spectral karyotyping and fluorescence in situ hybridization using subtelomeric probes permitted the full characterization of the cytogenetic abnormality. The additional material on 3q was found to originate from 14q31-qter.

Pathogenetics of 45,X/46,XY gonadal mosaicism.

Five patients with 45,X/46,XY mosaicism ranging from 8% to 66% of 46, XY lymphocytes in the peripheral blood were studied. Their age when chromosome studies were performed ranged from a few days to 37 yr. The phenotypic presentations were two females with gonadal dysgenesis and Turner syndrome features (cases 1 and 2), two males with ambiguous genitalia and mixed gonadal dysgenesis (cases 3 and 4), and an infertile male with an atrophic testis (case 5).

The mobile nature of acrocentric elements illustrated by three unusual chromosome variants.

Variant chromosomes are polymorphic in areas that are rich in repeat sequences such as the pericentromeric regions or in the acrocentric short arm regions. The dynamic nature of these regions is evident in the polymorphisms they exhibit. In this paper three unusual variants are described: a chromosome 21 with additional material on its short arm, a chromosome 7 with an insertion in the short arm and a chromosome 2 with satellites at the end of the long arm.

c-myc amplification in a preleukemia patient with trisomy 4 and double minutes: review of the unique coexistence of these two chromosome abnormalities in acute myelogenous leukemia.

Cytogenetic analysis of the bone marrow from a woman with preleukemia showed an aberrant clone with trisomy 4, double minutes, and a translocation t(8;9)(q21;q34). Fluorescence in situ hybridization (FISH) demonstrated that the double minutes were c-myc amplifications. A review of six cases in the literature and the present case with trisomy 4 and double minutes showed a preponderance of females and that the patients were mostly elderly.

An infant with a mosaic 45,X/46,X,psu dic(Y) (pter-->q11.2::q11.2-->pter) karyotype and mixed gonadal dysgenesis studied for extent of mosaicism in the gonads.

AN infant with mixed gonadal dysgenesis was found to have a 45,X/46,Xpsu dic(Y) karyotype. A low level (8%) of mosaicism for the dic(Y) cell line was observed in peripheral blood lymphocytes and skin fibroblasts. The dicentric nature of the Y chromosome became apparent in fluorescence in situ hybridization studies.

Two sibs with Wolf-Hirschhorn and DiGeorge deletions resulting from an unbalanced chromosome rearrangement, 45,XX/XY, der(4)t(4;22) (p16.3;q11.2) mat,-22.

A mother with apparently balanced translocation between chromosomes 4 and 22 gave birth to two children (sib 1 and twin A) with 45,XX,der(4)t(4;22) (p16.3;q11.2)mat,-22 and 45,XY,der(4)t(4; 22(p16.

[Cryotherapy in retinopathy of prematurity].

Survey of therapeutical and preventive care of premature babies with retinopathy. We observed the children during 10 years (1982-1991). 144 children were cared for various degree of ROP.