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Myelodysplastic syndrome (MDS) is an adult hematological disease that evolves into acute myeloid leukemia (AML) in about 30% of the cases. The availability of a highly specific probe moved us to perform in patients affected with MDS/AML, associated with normal karyotype, painting and fluorescence in situ hybridization (FISH) analysis aimed to check the inositide-specific phospholipase C (PI-PLC) ß1 gene, a player in the control of some checkpoints of the cell cycle. Here we present a preliminary observation in which FISH analysis disclosed in a small group of MDS/AML patients with normal karyotype the monoallelic deletion of the PI-PLCß1 gene. On the contrary, PI-PLC ß4, another gene coding for a signaling molecule, located on 20p12.3 at a distance as far as less than 1Mb from PI-PLCß1, is unaffected in MDS patients with the deletion of PI-PLC ß1 gene, hinting at an interstitial deletion. The MDS patients, bearing the deletion, rapidly evolved to AML. The data suggest the possible involvement of PI-PLCß1 in the progression of the disease and pave the way for a larger investigation aimed at identifying a possible high-risk group among MDS patients with a normal karyotype.Leukemia (2004) 18, 1122-1126. doi:10.1038/sj.leu.2403368 Published online 15 April 2004 [ABSTRACT FROM AUTHOR]

Background: Anorectal malformations (ARMs) are a common pediatric surgical problem with an incidence of 1:1500 to 1:5000 live births. The phenotypical spectrum extends from anal stenosis to imperforate anus with or without anal fistula to persistent cloaca. They can manifest as either non-syndromic or syndromic conditions. Various environmental and genetic risk factors have been elucidated. The widespread use of genetic screening tests for the investigation of developmental disorders increased the recognition of copy number variants (CNVs) of the 1q21.1 region. Duplications have also been associated with a multitude of congenital anomalies, such as heart disease, short stature, scoliosis, urogenital, and ARMs, and they have also been found in healthy individuals. The aim of this manuscript is to contribute to the definition of the phenotype associated with 1q21.1 duplications., Case Presentation: The present case describes a male, referred to us for an ARM, in whom array-comparative genomic hybridization (array-CGH) identified 1q21.1 duplication inherited from his healthy mother. No other genetic test was performed on the patient., Conclusions: We propose considering genetic evaluation and analysis in patients with only one congenital malformation in order to eventually make an early diagnosis and a better quality of treatments.

Background: Small supernumerary marker chromosomes (sSMC) are additional centric chromosome fragments too small to be identified by banding cytogenetics alone. A sSMC can originate from any chromosome and it is estimated that 70% of sSMC are de novo, while 30% are inherited. Cases of sSMC derived from chromosome 5 (sSMC5) are rare, accounting for1.4% of all reported sSMC cases. In these patients, the most common reported features are macrocephaly, dysmorphic facial features, heart defects, growth retardation, hypotonia, and intellectual disability. Also sSMC derived from chromosome 8 are very rare and the phenotype of patients with sSMC8 is very variable. Common clinical features of the patients include developmental delay, mental retardation, intellectual disability, hypotonia, hypospadias, attention deficit hyperactivity disorders (ADHD), skeletal anomalies, dysmorphic facial features, and renal dysplasia. To the best of our knowledge, in literature there are no cases with coexistence of sSMC5 and sSMC8, so we reviewed the literature to compare cases with SMC5 and those with SMC8 separately. This study is aimed to highlight the unique findings of a patient with the coexistence of sSMC5 and sSMC8., Case Presentation: We describe a female patient with two supernumerary markers derived from chromosome 5 (SMC5) and chromosome 8 (SMC8). The patient was born prematurely at 30 weeks with respiratory distress and bronchodysplasia. On physical examination she presented dysmorphic features, respiratory issues, congenital heart defect, developmental delay, and intellectual disability. The G-banded chromosome analysis on cultured lymphocytes revealed in all the analyzed cells a female karyotype with the presence of two supernumerary chromosomal markers and the array-CGH highlighted the region and the size of these two duplications. We also used the fluorescent in situ hybridization analysis (FISH) using painting of chromosomes 5 and 8 to confirm the origin of the two sSMC. So, the karyotype of the patient was: 48, XX, +mar1, +mar2., Conclusions: This is the first case with two markers: one from chromosome 5 and one from chromosome 8. Based on the data reported, we can affirm that the phenotype of our patient is probably caused mainly by the presence of the sSMC., (© 2022. The Author(s).)

Prenatal diagnosis plays a crucial role in clinical genetics. Non-invasive prenatal diagnosis using fetal cells circulating in maternal peripheral blood has become the goal of prenatal diagnosis, to obtain complete fetal genetic information and avoid risks to mother and fetus. The development of high-efficiency separation technologies is necessary to obtain the scarce fetal cells from the maternal circulation. Over the years, multiple approaches have been applied, including choice of the ideal cell targets, different cell recovering technologies, and refined cell isolation yield procedures. In order to provide a useful tool and to give insights about limitations and advantages of the technologies available today, we review the genetic research on the creation and validation of non-invasive prenatal diagnostic testing protocols based on the rare and labile circulating fetal cells during pregnancy.

Background: Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome (Online Mendelian Inheritance in Man [OMIM] #277000) is a congenital condition characterized by the total or partial agenesis of vagina and uterus. Agenesis can be isolated (MRKH 1) or associated with other renal, vertebral or cardiac defects (MRKH 2)., Case Presentation: In this paper, we report a case of a Caucasian patient showing the clinical signs associated with MRKH. Array-based comparative genomic hybridization (a-CGH) analysis revealed a microduplication of approximately 3.01 megabases (Mb) located on the long arm of chromosome 22 (22q11.21). Microduplications affecting the 22q11.21 region have been shown to be associated with MRKH syndrome and Müllerian aplasia. The phenotype of patients with 22q11.2 duplication (OMIM #608363) appears extremely variable, ranging from apparently normal to mild learning difficulties or with multiple defects, sharing features with DiGeorge/velocardiofacial (DGS/VCFS) syndrome., Conclusions: The altered gene expression together with other genetic, nongenetic, epigenetic or environmental factors can cause the extremely variable phenotype in patients carrying such duplication. Therefore, we can consider MRKH syndrome to be one of the clinical features of DGS/VCFS syndrome.

Over the past two decades, there has been a rapid evolution in prenatal screening for fetal chromosome abnormalities. Initially, testing was focused on the identification of affected pregnancies in either the first, or, the second trimester (e.g. the Combined test or the triple test). This was replaced by sequential modalities (e.g. contingent screening) that have enhanced detection while reducing the need for invasive testing. More recently, the introduction of technologies based on cell-free DNA (cfDNA) in maternal plasma and enrichment of fetal cells in maternal circulation have further refined the concept of sequential screening. In this review, we document our experience with serum and ultrasound-based contingent screening where we were able to achieve a detection rate of 96.8%, a false-positive rate of 2.8% and an odds of being affected given a positive result of 1:11. We also describe our initial experience with a novel sequential protocol that includes the analysis of fetal cells in maternal blood. Methods for enrichment for fetal cells cfDNA and cfDNA technologies offer the possibility of greater sensitivity and specificity as well as expansion in the scope of genetic disorders detectable. As costs decline, these technologies will become increasingly used as primary screening tools. In the meantime, sequential use offers a practical approach to maximizing the benefits of prenatal testing.

From January 1st 2013 to August 31st 2016, 24408 pregnant women received the first trimester Combined test and contingently offered second trimester maternal serum screening to identify those women who would most benefit from invasive prenatal diagnosis (IPD). The screening was based on first trimester cut-offs of ≥1:30 (IPD indicated), 1:31 to 1:899 (second trimester screening indicated) and ≤1:900 (no further action), and a second trimester cut-off of ≥1:250. From January 2014, analysis of fetal cells from peripheral maternal blood was also offered to women with positive screening results. For fetal Down syndrome, the overall detection rate was 96.8% for a false-positive rate of 2.8% resulting in an odds of being affected given a positive result (OAPR) of 1:11, equivalent to a positive predictive value (PPV) of 8.1%. Additional chromosome abnormalities were also identified resulting in an OAPR for any chromosome abnormality of 1:6.6 (PPV 11.9%). For a sub-set of cases with positive contingent test results, FISH analysis of circulating fetal cells in maternal circulation identified 7 abnormal and 39 as normal cases with 100% specificity and 100% sensitivity. We conclude that contingent screening using conventional Combined and second trimester screening tests is effective but can potentially be considerably enhanced through the addition of fetal cell analysis.

Background: A long sought goal in medical genetics has been the replacement of invasive procedures for the detection of chromosomal aneuploidies by isolating and analyzing fetal cells or free fetal DNA from maternal blood, avoiding risk to the fetus. However, a rapid, simple, consistent, and low-cost procedure suitable for routine clinical practice has not yet been achieved. The purpose of this study was to assess the feasibility of predicting fetal aneuploidy by applying our recently established dual-probe FISH protocol to fetal cells isolated and enriched from maternal blood., Methods: A total of 172 pregnant women underwent prospective testing for fetal aneuploidy by FISH analysis of fetal cells isolated from maternal blood. Results were compared with the karyotype determined through invasive procedures or at birth., Results: Seven of the samples exhibited fetal aneuploidy, which was confirmed by invasive prenatal diagnosis procedures. After enrichment for fetal cells, the frequency of trisomic cells was at least double in samples from aneuploid pregnancies (range 0.38-0.90%) compared to samples from normal pregnancies (≤0.18%). One false negative result was also obtained., Conclusions: Noninvasive prenatal aneuploidy screening using fetal cells isolated from maternal blood is feasible and could substantially reduce the need for invasive procedures.

A 40-year-old woman presented in her second pregnancy, naturally conceived. Maternal serum screening and ultrasound examination raised concerns regarding aneuploidy. After genetic counselling an amniocentesis was performed, showing a 69,XXX karyotype.Here we report a case of digynic triploidy, which resulted from fertilization of a diploid ovum by a single sperm.

We report on an apparently normal 5-month-old boy with a X;Y complex rearrangement identified first on prenatal diagnosis and found on array-CGH to have a 7.6 Mb duplication of Xp22.3 chromosome and a deletion of Yq chromosome, distal to the AZFa locus. Karyotype analysis on amniotic fluid cell cultures revealed a de novo homogenous chromosome marker that we interpreted as an isochromosome Yp. FISH analysis using SRY probe revealed only one signal on the derivative Y chromosome. The final karyotype was interpreted as 46,X,der(Y)t(X;Y)(p22.31;q11.22). Translocation Xp22;Yq11 in male are very rare event and only 4 cases have been published, all showing mental retardation and malformations. Herein we discussed some possible explanation for this apparent phenotypic variability., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Case Report: A fetus with rhombencephalosynapsis and prenatally diagnosed tetrasomy 9p is reported. Chromosomal analysis from amniocyte culture revealed non-mosaic supernumerary chromosome identified as isochromosome 9p (9p24-->q13::q13-->p24). Ultrasound scan revealed intrauterine growth retardation, renal anomalies, cardiac anomalies, ventriculomegaly, and agenesis of cerebellar vermis with fusion of the cerebellar hemispheres., Conclusion: Although most cases of cerebellar vermis agenesis in tetrasomy 9p are described with cystic malformation such as Dandy-Walker anomaly, our case indicates that this chromosomal disorder should be taken into account in fetuses with the development of cystic and non-cystic malformations of cerebellar vermis and posterior fossa.

Supernumerary invdup(15) chromosomes, now also reported as sSMC(15), containing two additional copies of Prader-Willi/Angelman critical region (PWACR) have been associated with distinct clinical phenotype that includes hypotonia, dysmorphisms, developmental delay/mental retardation, autistic behaviour, and epilepsy. We report on a healthy adult male carrying an sSMC(15) with two copies of PWACR in 20-50% of cells from different tissues. Molecular analyses showed the sSMC(15) as resulting from a PWACR-duplicated region spanning 8Mb which is larger than those in the only two other healthy PWACR-duplicated sSMC(15) carriers previously reported. Mosaicism level and mosaic cell line rate variation among different tissues observed in our case support mosaicism in critical tissues as of relevance for sSMC(15) phenotype-genotype correlations.

Deletions of the SHOX gene (Xp22-Yp11.3) are associated with Leri-Weill dyschondrosteosys (LWD) and idiopathic short stature. It has been estimated that SHOX deletions occur in 1,000-2,000 individuals in the total population, suggesting that this alteration should be investigated in all cases with unexplained short stature. SHOX deletions are currently investigated using fluorescence in situ hybridization (FISH) or molecular analysis of intragenic CA repeats. However, both techniques show some limitations. In the present study, the use of the multiple ligation probe amplification (MLPA) assay for the identification and characterization of SHOX deletions in 15 LWD patients, 3 of which carriers of chromosome abnormalities involving the SHOX gene, is reported. MLPA analysis demonstrated the heterozygous deletion of SHOX in seven patients (46.6%), disclosing the presence of two different proximal breakpoints. In patients with abnormal karyotype, MLPA analysis was able to identify the chromosomal rearrangement, showing, in addition to the SHOX deletions, the gain or loss of other genes mapped on the X and Y chromosomes. Since MLPA analysis can be carried out on a simple buccal swab, avoiding invasive peripheral blood collection, this technique represents a fast, simple and high throughput approach in the screening of SHOX deletions, able to provide more information as compared to FISH and microsatellite analysis.

The male-specific region (MSY) of the Y chromosome contains genes involved mainly in male sex determination and in spermatogenesis. The majority of genes involved in male fertility are localized in multiple copies in the long arm of the Y chromosome, within specific regions defined as "ampliconic regions." It has been suggested that these genes derived from X-linked or autosomal ancestors during evolution, providing a benefit for male fertility when transposed onto the Y chromosome. So far, the autosomal origin has been demonstrated only for two MSY genes, DAZ and CDY. In the present study we report on the identification within chromosome 8q11.2 of a region homologous to the g amplicon, containing the VCY2 (approved gene symbol BPY2), TTTY4, and TTTY17 genes. A search for ancestor genes within the 8q11.2 region allowed us to identify a gene named BEYLA and to characterize the genomic organization and the expression patterns of this gene.

Purpose: To identify the gene disrupted by a de novo reciprocal balanced translocation t(6;8)(q26;q13) in a patient with Duane retraction syndrome (DURS). The break point in chromosome arm 8q is positioned within the DURS1 critical region., Methods: Fluorescence in situ hybridization (FISH) analysis using cosmid and BAC clones covering the DURS1 locus was performed to define the break point position and its relationship with expressed sequence tags (ESTs) in the region. Once the interrupted gene was identified, the full-length cDNA was sequenced and the genomic organization defined. Eighteen patients with sporadic DURS without cytogenetic abnormalities involving the DURS1 region were screened for point mutations in the candidate DURS1 gene., Results: A carboxypeptidase gene (CPAH) was directly interrupted between the first and second exons in a patient with DURS who carried a de novo reciprocal balanced translocation t(6;8)(q26;q13) involving the DURS1 region on chromosome arm 8q13. The gene was transcribed in at least two alternative mRNA forms, with different start and stop codons., Conclusions: The CPAH gene was interrupted in a patient with DURS carrying a translocation break point in the DURS1 region on chromosome 8q13. CPAH is therefore a likely candidate for this abnormality, even if the possibility that other genes are involved, either by direct effects on transcription units present in the first CPAH intron or by position effects, cannot be ruled out. Functional studies of the influence of this gene on the morphogenesis of eye muscles and their innervation may clarify this question.

The C677T polymorphism of the MTHFR gene has been associated to maternal risk of Down syndrome, due to the detection of an higher prevalence of the T allele among mothers of children with trisomy 21, compared to control mothers. In order to confirm this association, we studied the presence of the C677T in 64 mothers of Down syndrome children and 112 controls from central Italy. An higher incidence of the mutant T allele in controls (48.2%) than in Down syndrome children mothers (44%) was detected. These results do not support the presence of an increased risk of Down syndrome in mothers carriers of the T allele in the Italian population.

VCY2 is a gene positioned within the AZFc locus of the Y chromosome, a region frequently deleted in infertile males. To investigate the involvement of this gene in idiopathic male infertility, we studied its genomic organization and localization. Analysis of the genomic structure demonstrated that the VCY2 gene is composed of 9 exons spanning 21 kb. FISH analysis on interphase nuclei with specific probes for exons 4-6, 7, and 8 demonstrated the presence of a single gene copy, and Fiber-FISH on relaxed chromatin indicated that VCY2 is located within the DAZ gene cluster. PCR, Southern blot, and FISH analysis on infertile patients with Yq microdeletions demonstrated the absence of VCY2 in all cases where deletions involved the DAZ gene, raising the question about the role of the VCY2 gene loss in the phenotype reported for DAZ-deleted patients., (Copyright 2001 Academic Press.)

Cytogenetic investigations and molecular analysis of the Y chromosome by the polymerase chain reaction amplification of sequence-tagged sites (STS-PCR) technique were performed in 126 patients affected by idiopathic oligo-azoospermia following accurate selection of cases. Seventeen patients evidenced an abnormal karyotype. Fourteen patients with a normal karyotype had microdeletions of the Y chromosome within interval 6. In azoospermic patients microdeletions were scattered along different subintervals, while in oligozoospermic patients they were clustered in subinterval 6E. The size of the deletion was not apparently related to the severity of the disease. These results suggest that cytogenetic analysis and the STS-PCR technique can detect a genetic cause of infertility in about one-quarter of patients with idiopathic oligo-azoospermia.

Three patients carrying an isodicentric (idic) Y chromosome associated with a mosaic 45,X cell line were studied using molecular techniques. Genotype-phenotype correlations suggested an effect of the 45,X cell line on sexual differentiation. A relationship was established between instability of the idic(Y) chromosome and localization of the breakpoint on Yq, and between azoospermia and deletion of interval 6 on Yq.

Two types of proteins play a major role in determining homologous desensitization of G-coupled receptors: beta-adrenergic receptor kinase (beta ARK), which phosphorylates the agonist-occupied receptor, and its functional cofactor, beta-arrestin. beta ARK is a member of a multigene family, consisting of six known subtypes, which have also been named G-protein-coupled receptor kinases (GRK 1 to 6) due to the apparently unique functional association of such kinases with this receptor family. The gene for beta ARK1 has been localized to human chromosome 11q13. The four members of the arrestin/beta-arrestin gene family identified so far are arrestin, X-arrestin, beta-arrestin 1, and beta-arrestin 2. Here we report the chromosome mapping of the human gene for beta-arrestin 1 (ARRB1) to chromosome 11q13 by fluorescence in situ hybridization (FISH). Two-color FISH confirmed that the two genes coding for the functionally related proteins beta ARK1 and beta-arrestin 1 both map to 11q13.