Willem Van de Ven

Cytogenetic and fluorescence in situ hybridization investigation of ring chromosomes characterizing a specific pathologic subgroup of adipose tissue tumors

Cytogenetic analysis of 184 adipose tissue tumors, 175 lipomas, and nine liposarcomas (LPS) showed the presence of a ring chromosome and/or a long marker chromosome in 10 cases with common histologic features such as atypical stromal cells with or without lipoblasts. In five of the cases, this appeared to be the sole cytogenetic abnormality. Fluorescence in situ hybridization (FISH) analysis with a microclone library specific for chromosome region 12q13-q15 showed extensive staining of the ring and long marker chromosomes, indicating that genetic sequences of this particular region of chromosome 12 are present in these marker chromosomes, most likely in an amplified form.

Chromosomal Anomalies in Individuals with Autism A Strategy towards the Identification of Genes Involved in Autism

We review the different strategies currently used to try to identify susceptibility genes for idiopathic autism. Although identification of genes is usually straightforward in Mendelian disorders, it has proved to be much more difficult to establish in polygenic disorders like autism. Neither genome screens of affected siblings nor the large number of association studies using candidate genes have resulted in finding autism susceptibility genes. We focus on the alternative approach of ‘positional cloning’ through chromosomal aberrations in individuals with autism. In particular, balanced aberrations such as reciprocal translocations or inversions offer a unique opportunity, since only the genes in the breakpoint regions are candidate genes. This approach, in combination with others, is likely to produce results in the coming years.

Involvement of a palindromic chromosome 22-specific low-copy repeat in a constitutional t(X; 22)(q27;q11)

Segmental duplications or low‐copy repeats (LCRs) on chromosome 22q11 have been implicated in several chromosomal rearrangements. The presence of AT‐rich regions in these duplications may lead to the formation of hairpin structures, which facilitate chromosomal rearrangement. Here we report the involvement of such a low‐copy repeat in a t(X;22) associated with a neural tube defect. Molecular analysis of the chromosomal breakpoints revealed that the chromosome 22 breakpoint maps in the palindromic non‐AT‐rich NF1‐like region of low‐copy repeat B (LCR‐B). No palindromic region was encountered near the breakpoint on chromosome X. Our findings confirm that there is no single mechanism leading to translocations with chromosome 22q11 involvement. Because LCR‐B does not contain genes involved in neural tube development, we believe that the gene responsible for the observed phenotype is most likely localized on chromosome X.

Carpal and tarsal synostoses and transverse reduction defects of the toes in two brothers heterozygous for a double de novo NOGGIN mutation

We describe two siblings with carpal and tarsal synostoses associated with transverse deficiencies of the toes. Mutation analysis of the NOG gene revealed a double missense mutation in both boys resulting in Pro42Ala and Pro50Arg. The parents were clinically unaffected, and these two mutations were not detected in their white blood cells or buccal mucosa. This indicates the presence of gonadal mosaicism or a low level of somatic mosaicism in one of the parents.

Is Curcumin for Monoclonal Gammopathy of Undetermined Significance without Risk? – Letter

Comment on: The potential role of curcumin in patients with monoclonal gammopathy of undefined significance--its effect on paraproteinemia and the urinary N-telopeptide of type I collagen bone turnover marker. [Clin Cancer Res. 2009]

Comment on: Monoclonal gammopathy of undetermined significance, smoldering multiple myeloma, and curcumin: a randomized, double-blind placebo-controlled crossover 4g study and an open-label 8g extension study.

Comment in: Response to Vermorken et al--curcumin and free light chains. [Am J Hematol. 2012] Comment on: Monoclonal gammopathy of undetermined significance, smoldering multiple myeloma, and curcumin: a randomized, double-blind placebo-controlled cross-over 4g study and an open-label 8g extension study. [Am J Hematol. 2012]