A new syndrome of microtia with unilateral renal agenesis and short stature.

We report on a 13-month-old girl of first cousin parents who presented with a combination of short stature, bilateral microtia, proportionate short stature, distinctive facial features (bitemporal narrowing, long philtrum), and agenesis of the left kidney and a small right kidney. Clinical findings did not match any previously described syndromes with the anomalies seen in the patient. We performed SNP array analysis to characterize the observation as a novel syndrome and this was normal.

A translocation in acute lymphoblastic leukemia that cytogenetically mimics the recurrent MLL-AFF1 translocation and fuses SEPT11 to MLL.

A 55-year-old man sought care for aggressive acute lymphoblastic leukemia (ALL), which developed 8 years after he had received chemotherapeutic treatment for nephrotic syndrome. The sole cytogenetic abnormality observed in bone marrow-derived metaphases was a t(4;11)(q21;q23), which is a frequently occurring translocation in ALL. However, subsequent reverse transcriptase-polymerase chain reaction for the expected mixed lineage leukemia [trithorax homolog, Drosophila] (MLL)-AFF1 fusion transcript was negative.

Spectral karyotypic and comparative genomic analysis of the endocrine pancreatic tumor cell line BON-1.

BON-1 is a human serotonin-producing endocrine pancreatic tumor (EPT) cell line, which has been used for various studies of tumorigenesis and treatment. Because its genotype, phenotype and degree of differentiation may underlie events that are instrumental to the development of endocrine tumors and, moreover, may vary between labs and over time, we decided to comprehensively characterize the chromosomal constitution of BON-1 by applying conventional GTG-banding, spectral karyotyping (SKY), comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). BON-1 cells proved to be hyperdiploid containing a modal chromosome number of 57 (range 56-64).

Identical cryptic partial monosomy 20pter and trisomy 20qter in three adult siblings due to a large maternal pericentric inversion: detection by MLPA and breakpoint mapping by SNP array analysis.

Genotypic and phenotypic data are presented on three adult siblings with mild to moderate mental retardation and mild dysmorphic features. All three siblings showed a chromosome 20 gain at the q-telomere and loss at the p-telomere in routine subtelomeric MLPA screening. Analysis of GTG-banded chromosomes did not detect any abnormalities, but subtelomeric fluorescent in situ hybridization (FISH) confirmed cryptic partial monosomy of chromosome region 20p13 --> 20pter and cryptic partial trisomy of chromosome region 20q13.

Prenatal identification of a marker chromosome 16 by chromosome microdissection and reverse FISH.

Prenatal cytogenetic analysis of cultured amniocytes was performed after an increased foetal nuchal translucency thickness was detected by ultrasound in week 17 of a pregnancy. Analysis of GTG-banded chromosomes showed a small marker chromosome in six of the 12 colonies analysed. The supernumerary abnormal chromosome appeared to be positive with DA/DAPI staining and C-banding.

Mosaic trisomy (8)(p22 --> pter) in a fetus caused by a supernumerary marker chromosome without alphoid sequences.

Objective: Our objective was to characterise a marker chromosome in cultured amniocytes of a fetus with a mos 47,XX,+mar[3]/46,XX[14] karyotype.

Methods: The indication for prenatal cytogenetic analysis of cultured amniocytes was advanced maternal age. Classic banding techniques (GTG- and C-banding) were performed.

A patient with a de novo 15q24q26.1 interstitial deletion, developmental delay, mild dysmorphism, and very blue irises.

We report on a patient with a de novo 15q24q26.1 interstitial deletion. She presented with developmental delay, behavioral characteristics, and mild dysmorphism with very blue irises.

A patient with a de novo 11q24.2-->qter deletion.

In the group of patients with terminal 11q deletion reported up to now. Jacobson syndrome has been delineated as a distinct clinical entity. In the present report we describe the clinical findings in a 3-year old girl with de novo deletion 11q24.

Characterization of a chromosome 8-derived minute marker chromosome using microdissection and FISH in a boy with growth retardation.

In a 9-year-old boy referred because of growth retardation, chromosome analysis showed the presence of a minute marker chromosome in 75% of the metaphases examined. The application of microdissection in combination with fluorescence in situ hybridization demonstrated that the marker was derived from the centromere region of chromosome 8, the karyotype being: mos 47,XY,+mar.ish der(8)(D8Z1+)[75]/46,XY[25].

Familial dup(8)(p12p21.1): mild phenotypic effect and review of partial 8p duplications.

We describe a family with direct transmission of a duplication of 8p12-->8p21.1. The phenotype of affected relatives included mild mental retardation but no minor anomalies.

Mosaic telomeric (2;14) association in a child with motor delay.

In a 6-year-old girl referred because of mild motor delay and hyperextensible joints, chromosome analysis disclosed a derivative chromosome consisting of end-to-end fusion of chromosomes 2 and 14. Two cell lines existed in which this telomere association was present, one with a 45,XX,tas(2;14)(q37;p11) karyotype and one with a 45,XX,tas(2;14) (q37;q32) karyotype. The cell line with the telomeric fusion of 2q and 14p was present in 90% of the cells; a telomeric fusion of 2q and 14q was seen in the remaining 10% of the cells.

Prenatally detected marker chromosome identified as an i(22)(p10) using (micro)FISH.

MicroFISH was used to elucidate the chromosomal origin of a prenatally detected marker chromosome. Five copies of the marker chromosome were collected from GTG-banded metaphases and amplified by means of DOP-PCR. The PCR product was labeled with blotine-14-dATP and used as a FISH probe for hybridization to metaphase chromosomes of the fetus (reverse painting).

Duplication of chromosome region 8p23.1-->p23.3: a benign variant?

Chromosome analysis was performed in a 34-year-old man who was phenotypically normal except for oligoasthenozoospermia. In this patient, analysis of GTG-banded chromosomes showed in one chromosome 8 additional chromosomal material of unknown origin. To characterize the aberrant chromosome more precisely, a paint specific for chromosome region 8pter-->8p23.

Complex chromosome 9, 20, and 22 rearrangements in acute lymphoblastic leukemia with duplication of BCR and ABL sequences.

Cytogenetic analysis was performed on bone marrow cells from a 28-year-old woman who was diagnosed with acute lymphoblastic leukemia (ALL). Her karyotype was: 46,XX,t(9;22)(q34;q11)[6]/47, XX,+8,t(9;22)(q34;q11)[4]/47,XX,+8,t(9;22)(q34;q11),del(20)(q11)[2]/46, XX,t(9;22)(q34;q11),del[20](q11)[7]/45,XX,der(9)t(9;22)(q34;q11),-20,-22 , +mar1[8]/45,XX,der(9)t(9;22)(q34;q11),-20,-22,+mar2[3]. Both marker chromosomes are dicentric and have the same size and banding pattern but different primary constrictions.

Detection of a cryptic translocation t(13;20)(q34;p13) in an unexplained case of MCA/MR: value of FISH over high resolution banding.

Cryptic unbalanced chromosome rearrangements in the telomeric bands of the chromosomes may constitute a significant cause of unexplained mental retardation with or without congenital anomalies. We report on a boy with a terminal deletion of the long arm of chromosome 13, combined with a partial duplication of the short arm of chromosome 20, owing to a cryptic balanced translocation in his father. The karyotype of the father was 46XY,t(13;20)(q34;p13).

Characterization of a partial trisomy 16q with FISH. Report of a patient and review of the literature.

Characterization of a partial trisomy 16 q with FISH: Report of a patient and literature review: We report on a 28-year-old male patient with severe growth and mental retardation, severe behavioural problems, especially automutilation, and a spastic quadriplegia. He showed no specific dysmorphism. The karyotype was 46, XY, dir dup(16) (q11.

Duplication within chromosome region 15q11-q13 in a patient with similarities to Prader-Willi syndrome confirmed by region-specific and band-specific fish.

We report on a patient presenting with mental retardation and obesity and a proximal duplication of chromosome 15. The patient shared some clinical signs with Prader-Willi syndrome. With a region-specific paint, generated by microdissection, a duplication in region 15q11.

Two cases of partial trisomy 8p and partial monosomy 21q in a family with a reciprocal translocation (8;21)(p21.1;q22.3).

We report on two mentally retarded adults with an unbalanced karyotype resulting from a familial balanced translocation between chromosomes 8 and 21, t(8;21)(p21.1;q22.3).

A simple and efficient method for microdissection and microFISH.

A simple and efficient method for the dissection of (marker) chromosomes, (micro)nuclei, and chromosome regions is presented. Before microdissection, metaphases are overlaid with milli-Q water to rehydrate the chromosomes, which makes them soft and sticky. The dissected chromosome fragments are dissolved without proteinase-K or topoisomerase treatment and directly amplified using a degenerate oligonucleotide primed polymerase chain reaction (DOP-PCR).

Characterization of a de novo unbalanced translocation t(14q18q) using microdissection and fluorescence in situ hybridization.

We report on a patient with a de novo translocation between the long arms of chromosomes 14 and 18. The translocation was studied using microdissection in combination with fluorescence in situ hybridization (micro-FISH). Five copies of the chromosomes involved in the translocation were isolated by microdissection and amplified by means of degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR).

Alagille syndrome in a family with duplication 20p11.

Alagille syndrome (arteriohepatic dysplasia, AHD) is a well defined genetic disorder with five major features: distinctive facies, cardiovascular anomalies, paucity of interlobular bile ducts (PILBD), ocular anomalies and minor skeletal malformations. Repeatedly, structural anomalies of 20p, in most cases a deletion, have been described in patients with Alagille syndrome. We report a three generation family with AHD presenting with typical facial dysmorphology, cardiac and ocular lesions but without clinical signs of liver manifestation.