Terminal deletion of chromosome 4 (4q deletion syndrome) is a rare genetic condition that is characterized by a broad clinical spectrum and phenotypic variability. Diagnosis of the distinct condition can be identified by conventional chromosome analysis and small deletions by novel molecular cytogenetic methods such as microarray comparative genome hybridization (aCGH). Prenatal diagnosis is challenging; to date 10 cases have been described. We report a prenatally diagnosed case of de novo 4q deletion syndrome confirmed by conventional karyotyping and FISH due to an elevated combined risk for Down syndrome and prenatal ultrasound findings. aCGH validated the diagnosis and offered exact characterization of the disorder. Cytogenetic and microarray results described a 4q32.1qter terminal deletion of the fetus. Prenatal ultrasound detected multiple nonstructural findings (micrognathia, choroid plexus cysts, echogenic fetal bowel, short femur, and cardiac axis deviation). Pregnancy was terminated at 20 weeks. In addition to the index patient, we reviewed the 10 prenatally published cases of 4q deletion syndrome in the literature and compared these with our results. We summarize the patients' characteristics and prenatal clinical findings. Alterations of maternal serum biochemical factors, an elevated combined risk for trisomies, and distinct ultrasonographic findings can often be observed in cases of prenatal 4q deletion syndrome and may facilitate the otherwise difficult prenatal diagnosis.

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A case of prenatally diagnosed Yq deletion is described. Fluorescence in situ hybridisation (FISH) was used to identify the abnormal chromosome and to exclude mosaicism. Based on the cytogenetic result and the ultrasound investigation the pregnancy was continued. A newborn with normal male genitalia was delivered. Microdeletion analysis of the Yq showed the absence of the AZFc region. This type of deletion has been described as being associated with azoospermia or oligozoospermia with a progressive decrease of sperm number over time. Long-term andrological follow-up of the newborn will be necessary with eventual cryoconservation of sperm at early adulthood. The present report proposes that AZF analysis combined with FISH has an important role in accurate genetic counselling in sex chromosome anomalies.

We report the prenatal exclusion of partial trisomy in a family with maternal pericentric inversion of chromosome 21 by fluorescence in situ hybridization (FISH). After determining the structural rearrangement in the mother and her affected son with 46,XY,rec(21)dup(21q)inv(21)(p11q22) resulting in Down syndrome (DS), a chorionic villus sample from the current pregnancy was analysed for the copy number of the DS critical region with a cosmid contig. The signal distribution was normal and the cytogenetic analysis revealed that the fetus had inherited the inverted chromosome 21 in a balanced form. FISH probes specific for the DS region are of great value in supporting cytogenetic results, regardless of the structural status of chromosome 21.

Authors report a case of mixed gonadal dysgenesis with a karyotype containing an isodicentric Y chromosome in mosaic form, which was diagnosed in an infant. They emphasize the necessity of the special investigations of newborn with perineoscrotal hypospadia and bilateral or unilateral maldescent testes immediately after birth. The result of accurate evaluation provides correct sex assignment and the prevention of the neoplastic degeneration of a dysgenetic gonad.