Jumping translocation in a phenotypically normal female.

"Jumping translocation" jt refers to a rare type of chromosome mosaic, in which the same portion of a (donor) chromosome is translocated to different (recipient) chromosome sites. Jt have mainly been observed in lymphocyte cultures of patients with hematologic malignancies. We report a phenotypically normal female carrying a mosaic of two cell lines with the Xq26-qter segment translocated to the short arm of chromosomes 15 or 21 in peripheral blood lymphocytes.

Mucopolysaccharidosis type I: identification of 8 novel mutations and determination of the frequency of the two common alpha-L-iduronidase mutations (W402X and Q70X) among European patients.

A group of 46 European patients with mucopolysaccharidosis type I (MPS I) was screened for mutations of the alpha-L-iduronidase gene. The 2 common nonsense mutations, W402X and Q70X, were identified in, respectively, 37% and 35% of mutant alleles. Considerable differences were seen in the frequency of these 2 mutations in patients from North Europe (Norway and Finland) and other European countries (mainly The Netherlands and Germany).

Iduronate-2-sulfatase gene mutations in 16 patients with mucopolysaccharidosis type II (Hunter syndrome).

Mutations of the iduronate-2-sulfatase gene were identified in 16 patients with mucopolysaccharidosis type II (Hunter syndrome). Together with another 10 cases reported by us earlier it emerges that about 20% of the patients have deletions of the whole gene or other major structural alterations. One, two or three base pair deletions are found in about 23% of the cases while the remaining about 57% carry point mutations predicting amino acid replacement, premature termination of translation, or aberrant splicing.

Polyploidies in abortion material decrease with maternal age.

Among 639 spontaneous abortions between the 8th and 14th week of gestation 342 (53.5%) revealed an abnormal karyotype. While the rate of trisomies distinctly increased with advancing maternal age, a decrease in the rate of 45,X conceptuses and polyploidies was observed among abortions from older women.

[Chromosomal mosaicism after diagnostic chorionic villi biopsy. Subsequent study of the placenta].

Among 311 diagnostic chromosomal analyses after CVS eleven results (mostly chromosomal mosaicism) did not fit completely with the chromosomal sets found in the fetuses and newborns. In all cases chromosomal mosaicism was restricted to the placenta only. All children born after the diagnosis of a chromosomal mosaicism in the placenta were normal.