Biomedical subjects

N Van Roy

Publications and source records attributed to N Van Roy.

69 records · Page 4Linked to original sources

PubMed1994

The human MCP-3 gene (SCYA7): cloning, sequence analysis, and assignment to the C-C chemokine gene cluster on chromosome 17q11.2-q12.

Monocyte chemotactic proteins (MCPs) are chemokines involved in macrophage recruitment during inflammation and cancer. A full-size MCP-3 cDNA was used to isolate the functional human MCP-3 gene. Based on restriction analysis, subclones were selected and the MCP-3 gene sequence was completed. In addition to a dense region with direct and inverted repeats and palindromic sequences, a double microsatellite (CA)n-(GA)n' was found at the 5'-end of the MCP-3 gene, and an RFLP was detected. The gene was regionally mapped by fluorescence in situ hybridization to human chromosome 17, subbands q11.2-q12. This site contains the MCP-subset of C-C chemokines and can be distinguished from the syntenic MIP-1 alpha locus. SCYA7 was assigned as the locus symbol of the MCP-3 gene. Double-labeling experiments confirmed the regional assignment of the MCP-3 gene close to the ERBB2 locus on human chromosome 17.

Amino Acid Sequence↗

PubMed1994

1;17 translocations and other chromosome 17 rearrangements in human primary neuroblastoma tumors and cell lines.

We report on the finding of a t(1;17) in two primary neuroblastomas. Subsequent fluorescence in situ hybridization (FISH) analysis revealed the presence of 1;17 translocations in four out of nine neuroblastoma cell lines. The chromosome 1 short arm breakpoints were determined using region-specific probes. FISH screening also demonstrated or confirmed the presence of 11;17 translocations in three cell lines and other chromosome 17 rearrangements in those cell lines that did not carry a t(1;17) or t(11;17). Our data extend previous cytogenetic findings and suggest that, in addition to the known involvement of chromosome 1, one or more genes on chromosome 17 also play a role in neuroblastoma development.

Adrenal Gland Neoplasms↗

PubMed1994

Direct transmission of a tandem duplication in the short arm of chromosome 8.

A family is described in which a mother and her two children carry a tandem duplication of the short arm of chromosome 8. Their phenotypes are similar and characterised by distinct facial dysmorphism, small stature and mild mental retardation. This is one of the first cases of direct familial transmission of a partial duplication of an autosomal chromosome segment.

Adult↗

PubMed1993

High-resolution fluorescence mapping of 46 DNA markers to the short arm of human chromosome 1.

We describe a high-resolution cytogenetic map for 46 DNA markers previously assigned to the short arm of human chromosome 1. Using fluorescence in situ hybridization on simultaneously R-banded prometaphase chromosomes, a refined map position was found for 45 probes. For 6 of these probes, additional hybridization sites were observed and for another 7 probes, conflicting results were found with regard to previous localizations. For some probes with overlapping map positions, probe order could be determined by dual-color hybridization on elongated chromosomes. The present high-resolution map can be used to refine the previously published composite map and also provides additional landmarks for the construction of a contig map of the short arm of chromosomes 1.

Chromosome Mapping↗

PubMed1993

Molecular cytogenetic analysis of a familial pericentric inversion of chromosome 12.

We describe the application of multi-color fluorescence in situ hybridization (FISH) in the characterization of a familial pericentric inversion. Using chromosome 12 short- and long-arm specific DNA probes, fast and reliable discrimination between normal and inversion chromosome 12 or recombinant inversion chromosome 12 was possible. FISH thus provides a reliable means for prenatal detection of balanced or unbalanced chromosome 12 rearrangements in this family. This approach is possible for identification of similar chromosome rearrangements provided that probes for the putatively involved chromosome region are available.

Adult↗

PubMed1992

Molecular cytogenetic analysis of a complex t(10;22;11) translocation in Ewing's sarcoma.

Fluorescence in situ hybridization (FISH) using chromosome-specific plasmid libraries and chromosome region-specific DNA markers allowed the characterization of a t(10;22;11) (p11.2;q12;q24) in a Ewing's sarcoma (ES). This study illustrates the usefulness of molecular cytogenetic analysis of ES, especially for determining the localization of the translocated 11q24-25 segment in complex or variant translocations.

Adult↗

PubMed1992

Reciprocal translocation between the proximal regions of the long arms of chromosomes 13 and 15 resulting in unbalanced offspring: characterization by fluorescence in situ hybridization and DNA analysis.

We describe two female siblings with similar clinical features consisting of hydrocephalus, scaphocephaly, hypotonia, mongoloid eye slant, blepharophimosis, micrognathia, supernumerary mouth frenula and mental retardation. Routine cytogenetic studies in the elder patient did not reveal any abnormality, and initially it was assumed that the syndrome had an autosomal recessive inheritance. However, a slightly larger chromosome 13 was seen in routine G-banded metaphases of the mother and the youngest of the two siblings. A shorter chromosome 15 was detected in the mother only. High resolution banding showed that the abnormal chromosome 13 contained an extra G-positive band at 13q12. The short chromosome 15 in the mother appeared to have a deletion of band q12. Fluorescence in situ hybridization using DNA markers specific to chromosomes 13 and 15 unequivocally showed that the mother was a carrier of a balanced reciprocal translocation t(13;15)(q12;q13), whereas the youngest sibling's karyotype was 46,XX,-13,+der(15)t(13;15)(q12;q13)mat, resulting in partial monosomy 13pter----q12 and partial trisomy 15pter----q13. The proband is thus trisomic for the critical region responsible for Prader-Willi syndrome and Angelman syndrome; this was confirmed by DNA analysis demonstrating one paternal and two maternal alleles from multiallelic marker loci mapping to 15q11-q13. This report illustrates the sensitivity and specificity offered by fluorescence in situ hybridization and its usefulness in the diagnosis and delineation of subtle chromosomal rearrangements.

Abnormalities, Multiple↗

PubMed1992

Molecular cytogenetic analysis of XX males using Y-specific DNA sequences, including SRY.

XX maleness is the most common condition in which testes develop in the absence of a cytogenetically detectable Y chromosome. Using molecular techniques, it is possible to detect Yp sequences in the majority of XX males. In this study, we could detect Y-specific sequences, including the sex-determining region of the Y chromosome (SRY), using fluorescence in situ hybridization. In 5 out of 6 previously unpublished XX males, SRY was translocated onto the terminal part of an X chromosome. This is the first report in which translocation of an SRY-bearing fragment to an X chromosome in XX males could be directly demonstrated.

Adolescent↗

PubMed1992

Uterine leiomyoma cytogenetics. III. Interphase cytogenetic analysis of karyotypically normal uterine leiomyoma excludes possibility of undetected trisomy 12.

Uterine leiomyoma, a benign tumor that histopathologically is rather homogeneous, was recently characterized cytogenetically. About 40% of the investigated tumors are associated with clonal chromosome abnormalities and five different subgroups have been identified, characterized by trisomy 12, t(12;14)(q14-15;q23-24), del(7q), t(1;2)(p36;p24), and 6p rearrangements. In our survey of 76 cases, trisomy 12 was observed in 10% of the abnormal cases. To exclude a possible underscoring of this abnormality, we reexamined 15 of the cases with normal karyotype by interphase cytogenetics using a chromosome 12 alphoid DNA probe.

Chromosomes, Human, Pair 12↗

PubMed1992

Putative monosomy 21 in two patients: clinical findings and investigation using fluorescence in situ hybridization.

Complete monosomy 21 is claimed to be a rare chromosomal disorder in which the cytogenetic investigation is bedevilled by technical difficulties. We describe the disparate clinical features in two patients in whom an initial diagnosis of monosomy 21 was made by routine karyotyping. Fluorescence in situ hybridisation (FISH) confirmed a translocation of chromosome 21 material to the short arm of chromosome 5 and to the X chromosome, respectively. The usefulness of FISH in the investigation of subtle chromosomal rearrangements is hereby demonstrated. These findings also cast doubt on the existence of "pure" monosomy 21 as an entity, and suggest that partial monosomy 21 is a more likely occurrence.

Abnormalities, Multiple↗

PubMed1992

Detection of subtle reciprocal translocations by fluorescence in situ hybridization.

Three different subtle reciprocal translocations were detected on long, well-banded chromosomes. The same translocations were examined using fluorescence in situ hybridization (FISH) with chromosome-specific libraries and unique DNA sequences. Our findings show that FISH allows rapid and unequivocal detection and characterization of this type of chromosome rearrangement. This approach is especially useful for prenatal diagnosis when one of the parents is a balanced carrier of such small fragment translocations.

Adult↗

PubMed1992

Interstitial deletion and ring chromosome derived from 19q. Proximal 19q trisomy phenotype.

A small supernumerary ring chromosome has been found in a boy with overweight, dysmorphic facies and mental retardation. His mother had an interstitial deletion of the long arm of chromosome 19 and the same ring chromosome. By means of fluorescence in situ hybridization the ring chromosome was shown to be derived from the deleted chromosome, after the occurrence of two breaks: one in the centromere region, the other in the q-arm of chromosome 19.

Abnormalities, Multiple↗

PubMed1991

Pallister-Killian syndrome: characterization of the isochromosome 12p by fluorescent in situ hybridization.

The isochromosome 12p (i(12p)) in fibroblasts of 3 patients with Pallister-Killian syndrome and one decreased prematurely born neonate, was characterized by fluorescent in situ hybridization (FISH) using chromosome 12-specific DNA probes. FISH is a useful technique for rapid and reliable detection and characterization of the i(12p) chromosome in Pallister-Killian patients. Detection was possible also in interphase cells. In addition, the in vitro selection against i(12p) cells at different passages in fibroblast cultures of two patients was monitored.

Abnormalities, Multiple↗

PubMed1991

Is t(6;20)(p21;q13) a characteristic chromosome change in endometrial polyps?

Cytogenetic analysis of an endometrial polyp showed the presence of a t(6;20)(p21;q13) together with an ins(16;1)(q22;q32q42). Since a 6;20-translocation has been previously found in another endometrial polyp, we think that t(6;20)(p21;q13) may be a characteristic chromosomal change in endometrial polyps.

Biomarkers, Tumor↗

PubMedDate not supplied

Identification and characterization of a novel member of the EXT gene family, EXTL2.

Recently, two homologous genes, EXT1 and EXT2, with a putative tumor suppressor function have been described. Mutations in both genes are responsible for multiple exostosis syndrome (EXT), an autosomal dominant condition characterized by the presence of multiple osteochondromas, bony excrescences that sometimes undergo malignant transformation to chondrosarcoma. This family of EXT genes has been extended by the identification of an EXT-like (EXTL) gene showing a high degree of homology with the EXT genes. We report here a second EXT-like gene (EXTL2) which is homologous to the EXT and EXTL genes. EXTL2 consists of 5 exons encoding an ubiquitously expressed protein of 330 amino acids. In addition, a putative pseudogene, EXTL2P was also identified. The EXTL2 gene was assigned to chromosome 1p11-p12, whereas EXTL2P was mapped on chromosome 2q24-q31.

Amino Acid Sequence↗