Identification of a family with nonspecific mental retardation (MRX79) with the A140V mutation in the MECP2 gene: is there a need for routine screening?

Mutations in the methyl-CpG-binding protein 2 (MECP2) cause Rett syndrome, a severe neurodevelopmental disorder occurring predominantly in females. Male patients with Rett syndrome are extremely rare, as the Rett-causing mutations in the MECP2 gene are usually lethal in hemizygous males. However, different mutations in the same gene were reported to cause mental retardation, both in sporadic non-syndromic males as well as in syndromic families with disease manifestation in carrier females.

Need for search for cryptic translocation in parents with several children affected with MCA: report of a cryptic translocation (10;14) detected by FISH.

The 3 affected children from 2 different wedlocks of the mother have been previously described (11). Search by FISH analysis in the mother revealed she is a carrier of balanced translocation of clear terminal G bands of equal sizes of the long arms of chromosomes 10 and 14. Chromosomal slides of the last child (Patient 3) could be analysed by fish and revealed that he did inherit the derivative chromosome 10.

[Prenatal diagnosis using amniocentesis and chorionic villi sampling: comparative study of chromosomal findings].

The authors report the results of chromosomal analyses performed on 6235 amniocenteses and 559 choriocenteses. Whereas the frequencies of chromosomal anomalies observed respectively on amniocenteses and choriocenteses did not differ significantly, the comparison of the types of aberrations found revealed, in chorion villi, a relatively high proportion of lethal anomalies, never encountered in amniocyte cultures. Furthermore, chromosomal mosaicism was observed 10 times more frequently on chorion villi than on amniotic cells.

[The role of genetic counseling in reproduction decisions].

In the literature dealing with the impact of genetic counsel in the reproduction decision, two aspects are discussed: 1. memorization and appraisal of the recurrence risk, chosen options for family planning, appraisal of genetic counsel by the patients 2. mechanisms of decision making and psychological impact of genetic counsel.

[Genetic counseling: evaluation of 1000 records].

1000 cases of genetic counseling have been reviewed. Most patients are sent to the genetic center by gynecologists (68.4%), mostly because of a personal or previous familial history (64%).