1/4. Molecular cytogenetic characterization of multiple intrachromosomal rearrangements of chromosome 2q in a patient with Waardenburg's syndrome and other congenital defects.At 6 years of age, a boy with bilateral sensorineural deafness, lateral displacement of inner canthi, a bulbous nasal tip, synophrys, and cryptorchidism was clinically diagnosed as having Waardenburg's syndrome type I (WS-1). In addition, he had a lumbar spina bifida with hydrocephalus shunted on the second day of life and severe mental retardation with a head circumference at the fifth percentile. Neither parent showed signs of WS-1, and the family history was negative. Because of the WS-1 features, attention was focused on the PAX3 location in 2q, at which time a de novo paracentric inversion of 2q23-q37.1 was noted. Subsequent high-resolution chromosome analysis 8 years later indicated a complex rearrangement involving regions 2q31-q35 and 2q13-q21. Whole chromosome painting and high-resolution comparative genomic hybridization yielded negative results for any translocation, duplication, or deletion of any chromosome segments. Sequencing of the PAX3 gene yielded no detectable mutation. Fluorescent in situ hybridization (FISH) studies with human BAC clones revealed five breakpoints in chromosome 2q resulting in two paracentric inversions and one insertion, the karyotype being interpreted as 46,XY,der(2)inv(2)(q13q21)inv(2)(q21q24.2)ins(2)(q24.2q33q35). In this extremely rare chromosomal rearrangement, the FISH result showed a breakpoint at 2q35 being proximal to and without involvement of the PAX3 gene. While further studies continue, possible interpretations include involvement of a regulatory gene(s) for PAX 3 and other genes at the other breakpoints related causally to the spina bifida and mental retardation.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/4. Virus detection in the fetal tissue of a premature delivery with a congenital varicella syndrome. A case report.Cases of congenital varicella syndrome have been published, to date, a single case reports. Isolation attempts of Varicella-Zoster virus from fetal tissues have, thus far, been unsuccessful. This is a first report of detection of Varicella-Zoster virus in fetal tissue by means of dna hybridization technique in a typical case of congenital varicella syndrome in a premature delivery of the 27th gestational week. The case is documented anamnestically, sonographically, pathologically and virologically. In women with primary varicella infection during pregnancy good sonographical controls are recommended. In cases with sonographically characteristical signs prenatal diagnosis with puncture of the umbilical vein cord and placentocentesis may be considered. The varicella dna detection should be supplemented, however, by the polymerase chain reaction.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
3/4. Dandy-Walker malformation in a fetus with pentasomy X (49,XXXXX) prenatally diagnosed by fluorescence in situ hybridization technique.We present the case of a pentasomy X (49,XXXXX) prenatally diagnosed. The fluorescent in situ hybridization technique assisted in making the diagnosis. The problems identified in this fetus include a Dandy-Walker malformation, hydrocephaly, ventricular septal defect, hypertelorism and polyhydramnios.- - - - - - - - - - ranking = 2.5keywords = hybridization (Clic here for more details about this article) |
4/4. dna-based X-enriched sperm separation as an adjunct to preimplantation genetic testing for the prevention of X-linked disease.We report the world's first clinical pregnancy resulting from dna-based enrichment for X-bearing human spermatozoa, for prevention of X-linked hydrocephalus. Sperm separation was followed by embryo biopsy and nested multiplex polymerase chain reaction (PCR) for gender determination. Enriched populations of X-bearing spermatozoa ranging from 80 to 89% pure as determined by fluorescence in-situ hybridization (FISH) resulted in in-vitro fertilization (IVF) rates indistinguishable from normal IVF procedures (65%). In two separate biopsy procedures, 7/9 and 15/16 of the resulting embryos were determined to be female by multiplex PCR. embryo transfer resulted in a karyotypically normal female fetus. This technique should be widely applicable to gender selection for the prevention of genetic disorders.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |