Lowe syndrome identified in the offspring of an oocyte donor who was an unknown carrier of a de novo mutation: a case report and review of the literature.

BACKGROUND: Oculocerebrorenal syndrome of Lowe is an X-linked disorder with very low prevalence in the general population. The OCRL gene encodes the protein phosphatidylinositol 4,5-bisphosphate-5-phosphatase, a lipid phosphatase, located in the trans-Golgi network. Point mutations in the OCRL gene cause Lowe syndrome and Dent disease, which are characterized as a multisystemic disorder. The symptoms of Lowe syndrome are expressed primarily as dysfunction of the eyes, kidneys, and the central nervous system. CASE PRESENTATION: This report describes a case of a 31-year-old Georgian woman with a de novo pathogenic mutation causing oculocerebrorenal syndrome of Lowe, who was a volunteer in an oocyte donation program for in vitro fertilization purposes, and the outcome of the treatments of this particular donor's oocyte receivers, describing the implications of the mutation for the children born as a result of the treatments. It raises important medical and ethical issues about the necessity of genetic testing of oocyte donors and the possibility of rare genetic disorders being inherited by the offspring of donors. CONCLUSION: This particular case indicates the legal, medical, and emotional risks of utilizing donor oocytes from phenotypically healthy women, whose genetic constitution is unknown in terms of being silent carriers of rare diseases. In addition, all the necessary actions were followed; the further examinations that are required are mentioned. The donor and the offspring should be further tested. The remaining cryopreserved embryos should be destroyed or preimplantation genetic testing should be performed before they are utilized. Finally, all the people involved, the treated couples and the donor, alongside her family, should follow genetic and psychological counselling.

Partial monosomy14q involving FOXG1 and NOVA1 in an infant with microcephaly, seizures and severe developmental delay.

BACKGROUND: FOXG1 gene mutations have been associated with the congenital variant of Rett syndrome (RTT) since the initial description of two patients in 2008. The on-going accumulation of clinical data suggests that the FOXG1-variant of RTT forms a distinguishable phenotype, consisting mainly of postnatal microcephaly, seizures, hypotonia, developmental delay and corpus callosum agenesis. CASE PRESENTATION: We report a 6-month-old female infant, born at 38 weeks of gestation after in vitro fertilization, who presented with feeding difficulties, irritability and developmental delay from the first months of life. Microcephaly with bitemporal narrowing, dyspraxia, poor eye contact and strabismus were also noted. At 10 months, the proband exhibited focal seizures and required valproic acid treatment. Array-Comparative Genomic Hybridization revealed a 4.09 Mb deletion in 14q12 region, encompassing the FOXG1 and NOVA1 genes. The proband presented similar feature with patients with 14q12 deletions except for dysgenesis of corpus callosum. Disruption of the NOVA1 gene which promotes the motor neurons apoptosis has not yet been linked to any human phenotypes and it is uncertain if it affects our patient's phenotype. CONCLUSIONS: Since our patient is the first reported case with deletion of both genes (FOXG1-NOVA1), thorough clinical follow up would further delineate the Congenital Rett-Variant phenotypes.

A patient with partial trisomy 21 and 7q deletion expresses mild Down syndrome phenotype.

BACKGROUND: Down syndrome (DS) is the most common aneuploidy in live-born individuals and it is well recognized with various phenotypic expressions. Although an extra chromosome 21 is the genetic cause for DS, specific phenotypic features may result from the duplication of smaller regions of the chromosome and more studies need to define genotypic and phenotypic correlations. CASE REPORT: We report on a 26 year old male with partial trisomy 21 presenting mild clinical symptoms relative to DS including borderline intellectual disability. In particular, the face and the presence of hypotonia and keratoconus were suggestive for the DS although the condition remained unnoticed until his adult age array comparative genomic hybridization (aCGH) revealed a 10.1 Mb duplication in 21q22.13q22.3 and a small deletion of 2.2 Mb on chromosomal band 7q36 arising from a paternal translocation t(7;21). The 21q duplication encompasses the gene DYRK1. CONCLUSION: Our data support the evidence of specific regions on distal 21q whose duplication results in phenotypes recalling the typical DS face. Although the duplication region contains DYRK1, which has previously been implicated in the causation of DS, our patient has a borderline IQ confirming that their duplication is not sufficient to cause the full DS phenotype.

De novo 15.5-Mb Interstitial Deletion in 5p in a Male Ascertained by Oligospermia.

We describe a case of a 34-year-old male presenting with oligospermia and an otherwise normal phenotype. Investigation with array-based comparative genomic hybridization (aCGH) revealed an interstitial deletion of about 15.5 Mb in chromosome 5p13.3p14.3. We compared the phenotype of our patient with recently reported patients studied by aCGH, who show an overlapping deletion. We also analyzed the gene content of the deleted region in order to propose a possible involvement of specific genes in the clinical phenotype.

Partial trisomy 2p and partial monosomy 2q arising from a paternal intrachromosomal 2q-into-2p between-arm insertion and paracentric inversion: molecular cytogenetic characterization of a four-break rearrangement.

We report on a 26-month-old boy with an interstitial duplication of 2p22.3p22.2 and an interstitial deletion of 2q14.1q21.2. The abnormality was derived from his father having a balanced paracentric inversion and pericentric insertion. The deletion in the child was identified by cytogenetic analysis and characterized in more detail by molecular cytogenetics and array comparative genomic hybridization. The latter revealed a 20-Mb deletion in the long arm and a 5.6-Mb duplication in the short arm of chromosome 2. Fluorescence in situ hybridization in paternal chromosomes characterized an intrachromosomal insertion of 2q14.1q21.2 into 2p23; additionally a paracentric inversion of 2p13p23 was observed. The boy with the unbalanced karyotype suffered from severe psychomotor retardation, thrombophilia due to protein C deficiency, and hypertrophic cardiomyopathy and also had phenotypic abnormalities. Most of these features have previously been described in individuals with interstitial deletion of 2q14.1.

First trimester diagnosis of 13q-syndrome associated with increased fetal nuchal translucency thickness. Clinical findings and systematic review.

13q-syndrome is a rare chromosomal disorder caused by partial deletion of the long arm of chromosome 13 with variable phenotypic presentation. Further sonographic features involve fetal growth restriction, bradycardia, encephalocele, facial dysmorphism and upper extremity deformity. We report a case of 13q-syndrome presenting as increased nuchal translucency diagnosed by chromosome studies and confirmed by array comparative genomic hybridization (CGH) analysis in the first trimester of pregnancy. Pregnancy was terminated at 14 weeks' gestation. The parents did not give consent for a postmortem examination. Furthermore we performed a systematic review of the international literature on previous cases of 13q-syndrome diagnosed prenatally. Our case emphasizes the importance of a detailed 11-14 week ultrasound assessment in diagnosing fetal chromosomal aberrations in combination with the modern aspects of array CGH, thus providing more precise and rapid prenatal diagnosis.

Tetrasomy 9p mosaicism associated with a normal phenotype in two cases.

Tetrasomy 9p is a rare chromosomal syndrome and about 30% of known cases exhibit mosaicism. Approximately 50 of the reported cases with tetrasomy 9p mosaicism show a characteristic facial appearance, growth failure, and developmental delay. However, 3 patients with mosaicism for isochromosome 9p and a normal phenotype have also been reported. We report 2 additional cases of clinically normal young females with tetrasomy 9p mosaicism, one of whom also exhibited X chromosome aneuploidy mosaicism leading to an overall of 6 different cell lines. STR analysis performed on this complex mosaic case indicated that the extra isochromosome was of maternal origin while the X chromosome aneuploidy was of paternal origin, indicating a postzygotic event.

Non-trophoblastic tumor of the placenta with combined histologic features of chorangioma and leiomyoma.

Chorangioma is the most common non-trophoblastic tumor of the placenta, which represents an excessive vascular proliferation within chorionic villi. While the histologic picture of a chorangioma may vary greatly from lesion to lesion, the presence of abundant smooth muscle tissue within a chorangioma has not been previously reported. Herein we report a case of a 34-year-old primigravida woman with a peculiar mesenchymal placental tumor, characterized by combined features of chorangioma and leiomyoma; large lobules of numerous small blood vessels within loose stroma, separated by broad bundles of smooth muscle fibers. Genetic studies by means of PCR excluded maternal and confirmed placental origin of the lesion.

Characterization of 23 small supernumerary marker chromosomes detected at pre-natal diagnosis: The value of fluorescence in situ hybridization.

Small supernumerary marker chromosomes (sSMCs) cannot be identified or characterized unambiguously by conventional cytogenetic banding techniques. Until recently, the large variety of marker chromosomes, as well as the limitations in their identification, have presented a diagnostic problem. In order to determine the origin of sSMCs, we used a variety of fluorescence in situ hybridization (FISH) methods, including centromere-specific multicolor FISH, acrocentric specific multicolor FISH, subcentromere-specific multicolor FISH and multicolor FISH with whole chromosome paint probes. Moreover, uniparental disomy testing was in all cases attempted. From a total of 28,000 pre-natal samples from four diagnostic genetics laboratories in Greece, 23 (0.082%) supernumerary marker chromosomes were detected. The mean maternal age was 36.2 years (range 27-43) and the mean gestational age at which amniocentesis was performed was 18.5 weeks (range 16-23). Eighteen markers were de novo and 5 markers were inherited. Molecular cytogenetic methods were applied to determine the chromosomal origin and composition of the sSMC. In total, 17 markers were derived from acrocentric chromosomes (14, 15, 21 and 22) and 6 markers were non-acrocentric, derived from chromosomes 9, 16, 18, 20 and Y. Uniparental disomy was not detected in any of the cases studied. With regard to pregnancy outcome, 13 pregnancies resulted in normal healthy neonates, while 10 pregnancies were terminated due to ultrasound abnormalities. A total of 23 marker chromosomes from 28,000 pre-natal samples (0.082%) were identified. Molecular cytogenetic techniques provided valuable information on the chromosomal origin and composition of all the sSMCs. Especially in cases with normal ultrasound, the FISH results rendered genetic counseling possible in a category of cases previously considered a diagnostic problem. Abnormal outcome was observed in 10 cases (43,5%), 7 of which showed abnormal ultrasound findings. New technologies, such as array-comparative genomic hybridization, should be used in future genotype-phenotype correlation studies, although the high mosaicism rate poses a problem.