Prenatal diagnosis of 17p13.1p13.3 duplication.

We present here the first prenatal diagnosis of 17p13.1p13.3 duplication.

Further evidence for a relationship between the 5p15 chromosome region and the oculoauriculovertebral anomaly.

The oculoauriculovertebral anomaly (OAV) or Goldenhar syndrome is a malformation complex that has been described in several chromosomal rearrangements. Among them a deletion of the terminal 5p has recurred in seven previous patients. We wish to report on an additional such patient in order to reinforce the significance of this genomic region in the cause of at least a subgroup of OAV cases.

PAK3 related mental disability: further characterization of the phenotype.

We report clinical, neuropsychological and molecular findings in affected males and carrier females in the fourth reported family with mental retardation caused by mutation in the PAK3 gene (Xq22.3-q23), W446S. In contrast to previous reports, carrier females manifested learning problems and mild mental disability.

Identification of antibodies against HAI-1 and integrin alpha6beta4 as immunohistochemical markers of human villous cytotrophoblast.

Syncytiotrophoblast and invasive extravillous trophoblast arise from a common stem cell, namely villous cytotrophoblast, but have very different characteristics. The study of the differentiation process relies on the availability of suitable markers for these different cell types of developing placenta. In this work, we have produced monoclonal antibodies that are specific to human villous cytotrophoblast.

MECP2 mutation analysis in patients with mental retardation.

Mutations in the methyl-CpG-binding protein 2 (MECP2) gene are known to underlie Rett' syndrome, the most common cause of mental retardation (MR) in girls. Since the original report, phenotypes resulting from MECP2 mutations have been shown to extend, for example, to several Rett variants, autism, atypical Angelman syndrome, and nonspecific MR. It was earlier proposed that MECP2 mutations might account for approximately 2% of the male cases with nonspecific MR.

Expansion of the fragile X CGG repeat in females with premutation or intermediate alleles.

The CGG repeat in the 5' untranslated region of the fragile X mental retardation 1 gene (FMR1) exhibits remarkable instability upon transmission from mothers with premutation alleles. A collaboration of 13 laboratories in eight countries was established to examine four issues concerning FMR1 CGG-repeat instability among females with premutation (approximately 55-200 repeats) and intermediate (approximately 46-60 repeats) alleles. Our central findings were as follows: (1) The smallest premutation alleles that expanded to a full mutation (>200 repeats) in one generation contained 59 repeats; sequence analysis of the 59-repeat alleles from these two females revealed no AGG interruptions within the FMR1 CGG repeat.

Prenatally detected trisomy 7 mosaicism in a dysmorphic child.

Trisomy 7 mosaicism was detected prenatally in cultured amniocytes but not in fetal lymphocytes. The child that was born had pigmentary changes of the skin and facial asymmetry suggestive of a chromosomal mosaicism. Skin fibroblasts were studied and trisomy 7 mosaicism was confirmed.