Familial 3-Way Balanced Translocation Causes 1q43→qter Loss and 10q25.2→qter Gain in a Severely Affected Male Toddler.

Constitutional complex chromosomal rearrangements (CCRs) are rare events that typically involve 2 or more chromosomes with at least 3 breakpoints and can result in normal or abnormal phenotypes depending on whether they disturb the euchromatic neighborhood. Here, we report an unusual balanced CCR involving chromosomes 1, 9, and 10 that causes an unbalanced karyotype in a severely affected toddler. The CCR was initially reported as a maternal 2-way translocation but was reclassified as a 3-way translocation after a microarray analysis of the propositus revealed the involvement of another chromosome not identified by G-banding in his phenotypically normal mother. FISH assays on maternal metaphase cells confirmed that the 1qter region of der(1) was translocated to der(10), whereas the 10qter segment was translocated to der(9), which in turn donated a segment to der(1). Subsequently, this CCR was also identified in her phenotypically normal father (the patient's grandfather). Thus, the patient inherited the previously unreported pathogenic combination of der(1) with a loss of 1q43→qter (including AKT3, ZBTB18, HNRNPU, and SMYD3) and der(9) with a gain of 10q25.2→qter (including FGFR2), leading to a compound phenotype with key features of the 1q43→qter deletion and distal 10q trisomy syndromes. Our observations suggest that the loss of SMYD3 accounts for cardiac defects in a subset of patients. Moreover, due to recurrent miscarriages in this family, our findings allowed improved genetic counseling.

Cadmium, copper, lead, and zinc in Mugil cephalus from seven coastal lagoons of NW Mexico.

The increasing order of the mean concentrations of Cd, Cu, and Zn in the tissues of Mugil cephalus of seven coastal lagoons of Sinaloa State (NW Mexico) was liver > gills > muscle, while for Pb it was gills > muscle ≥ liver. There were no differences between the mean concentrations of Cd and Pb of the three tissues determined in the samples of the seven lagoons and, although there were some significant differences, there was no indication of a latitude-related trend in the distribution of Cu and Zn: the Cu content of the muscle tended to be higher in the northern than in the southern lagoons, although in the case of the gills the highest and lowest mean values indicated an opposite trend, with the highest and lowest values in one southern and one northern lagoon. In the case of the liver, there were no differences and no indication of a regional trend. There were no differences in the mean Zn contents of muscle and gills; in the case of the liver, one of the lagoons of the central part of the state had a significantly higher value than one of the southern lagoons and all the rest had similar values. In addition, there was no clear indication of season-related differences in any of the three tissues. According to our results, the metal contents of the muscle of this species are not of concern for human health, since the allowable ingestion would be in the order of 0.9 kg/day.

The metal content of bivalve molluscs of a coastal lagoon of NW Mexico.

The lagoonal system Altata-Ensenada del Pabellón supports important traditional fisheries and mollusc cultures and receives urban and agricultural effluents. The annual mean Cd contents of the oyster and mussel Crassostrea gigas and Mytella strigata of the inner mangrove swamps were higher than that of the clam Megapitaria squalida, which lives in areas under marine influence. Crassostrea corteziensis had the highest Cu and Zn contents, showing that it is a strong accumulator of both metals and especially of Zn, and there were no significant differences in the Pb content of the three species.