This retrospective cohort study aimed to define the optimal Regions of Homozygosity (ROH) size cut-offs for prediction of morbidity, based on 13 483 Chromosomal Microarray Analyses (CMA). Receiver operating characteristic (ROC) curves were generated, and area under the curve (AUC) was used to assess the predictive capability of total ROH percentage (TRPS), ROH number and ROH segment size in distinguishing between healthy (n=6,196) and affected (n=6,839) cohorts. The metrics were examined for telomeric and interstitial segments, distinct TRPS categories, and across different ancestral origins.
View Article and Find Full Text PDFThis study investigates distal 2q13 microdeletion, presenting the largest cohort to date, including prenatal cases, alongside a comprehensive literature review. A retrospective analysis was conducted on distal 2q13 microdeletions from clinical charts and laboratory reports. The cohort was divided into "clinically indicated" and "not-clinically indicated" groups based on the reason for chromosomal microarray testing.
View Article and Find Full Text PDFRegions of Homozygosity (ROH) typically reflect normal demographic history of a human population, but may also relate to cryptic consanguinity, and, additionally, have been associated with specific medical conditions. The objective of this study was to investigate the location, size, and prevalence of common ROH segments in a Middle Eastern cohort. This retrospective study included 13 483 samples collected from all Chromosomal Microarray analyses (CMA) performed using Single Nucleotide Polymorphism (SNP) arrays at the genetic clinical laboratory of Rabin Medical Center between 2017-2023 (primary data set).
View Article and Find Full Text PDFLong contiguous stretches of homozygosity or regions of homozygosity (ROH) are frequently detected via microarray and sequencing technologies. However, consensus on the establishment of specific size cutoffs for reporting ROH remains elusive. This study aims to assess the Total ROH Percentages (TRPS) and size of ROH segments across different ethnic origins, exploring potential disparities and proposing tailored diagnostic thresholds.
View Article and Find Full Text PDFObjective: This study aimed to assess the detection rate of clinically significant results of prenatal exome sequencing (pES) in low-risk pregnancies and apparently normal fetuses in non-consanguineous couples.
Methods: A retrospective analysis of pES conducted at a single center from January 2020 to September 2023 was performed. Genetic counseling was provided, and detailed medical histories were obtained.
Objective: This study aimed to determine the diagnostic yield of chromosomal microarray analysis (CMA) performed in cases of fetal abnormalities detected during the third trimester of pregnancy.
Study Design: A retrospective review of medical records was conducted for women who underwent amniocentesis at or beyond 28 weeks of gestation between January 2017 and February 2023. CMA results of pregnancies with abnormal sonographic findings not detected before 28 weeks were included.
Background: Distal Xq28 duplication, or int22h1/int22h2-mediated Xq28 duplication syndrome, leads to cognitive impairment, neurobehavioral issues, and facial dysmorphisms. Existing literature has limited information on clinical traits and penetrance.
Methods: We identified cases of distal Xq28 duplication (chrX: 154,126,575-154,709,680, GRCh37/hg19) through a review of clinical records and microarray reports from five centers, encompassing both postnatal and prenatal cases, with no prior family knowledge of the duplication.
Introduction: Microcephaly, characterized by abnormal head growth, can often serve as an initial indicator of congenital, genetic, or acquired disorders. In this study, we sought to evaluate the effectiveness of chromosomal microarray (CMA) testing in detecting abnormalities in both prenatal and postnatal cases of microcephaly.
Materials And Methods: CMA Testing: We conducted CMA testing on 87 prenatally-detected microcephaly cases and 742 postnatal cases at a single laboratory.
Objective: Significant discrepancy exists between laboratories in classification and reporting of copy number variants (CNVs). Studies exploring factors affecting prenatal CNV management are rare. Our "virtual fetus" pilot study examines these factors.
View Article and Find Full Text PDFAm J Obstet Gynecol MFM
December 2023
Background: The rate of clinically significant copy number variants in chromosomal microarray analysis in low-risk pregnancies is approximately 1%. However, these results include copy number variants with low and variable penetrance, although some patients might be interested only in the detection of high-penetrant variants.
Objective: This study aimed to calculate the prevalence of high-penetrant copy number variants in a large cohort of low-risk pregnancies.
Proximal 1q21 microduplication is an incomplete penetrance and variable expressivity syndrome. This study reports 28 new cases and summarizes data on phenotype, gender, and parental origin. Data on isolated proximal 1q21.
View Article and Find Full Text PDFFor decades, prenatal screening and genetic testing strategies were limited, requiring less complex decisions. Recently, however, several new advanced technologies were introduced, including chromosomal microarray analysis (CMA) and non-invasive prenatal screening (NIPS), bringing about the need to choose the most appropriate testing for each pregnancy. A worrisome issue is that opposed to the wide implementation and debates over public funding of NIPS, currently invasive testing is still recommended only in selected pregnancies with increased risk for chromosomal aberrations (according to screening tests or sonographic anomalies).
View Article and Find Full Text PDFPurpose: Pathogenic variants in genes involved in the epigenetic machinery are an emerging cause of neurodevelopment disorders (NDDs). Lysine-demethylase 2B (KDM2B) encodes an epigenetic regulator and mouse models suggest an important role during development. We set out to determine whether KDM2B variants are associated with NDD.
View Article and Find Full Text PDFObjective: To examine the effect of maternal age on the rate of clinically significant chromosomal microarray analysis results in pregnancies with abnormal maternal serum screening and to establish the residual risk for abnormal microarray findings after omitting noninvasive prenatal testing (NIPT)-detectable aberrations in pregnancies with abnormal maternal serum screening.
Methods: This retrospective study included all chromosomal microarray analysis tests performed in pregnancies with abnormal maternal serum screening and normal ultrasonogram results over the years 2013-2021. The rate of clinically significant (pathogenic and likely pathogenic) chromosomal microarray analysis findings was compared with a local control cohort of 7,235 pregnancies with normal maternal serum screening and ultrasonogram results, stratified by maternal age.
Purpose: This study aimed to evaluate the prevalence of clinically significant (pathogenic and likely pathogenic) variants detected by chromosomal microarray (CMA) tests performed for prenatally and postnatally detected congenital heart defects.
Methods: A retrospective evaluation of CMA analyses over a period of four years in a single tertiary medical center was performed. Detection rate of clinically significant variants was calculated in the whole cohort, prenatal vs.
Background: Chromosomal microarray analysis detects a clinically significant amount of copy number variants in approximately 1% of low-risk pregnancies. As the constantly growing use of noninvasive prenatal screening has facilitated the detection of chromosomal aberrations, defining the rate of abnormal chromosomal microarray analysis findings following normal noninvasive prenatal screening is of importance for making informed decisions regarding prenatal testing and screening options.
Objective: To calculate the residual risk for clinically significant copy number variants following theoretically normal noninvasive prenatal screening.
Objective: We investigated the detection rate of clinically significant chromosomal microarray analysis (CMA) results in pregnancies with sonographic diagnosis of fetal corpus callosum anomalies (CCA) or posterior fossa anomalies (PFA).
Methods: All CMA tests in pregnancies with CCA or PFA performed between January 2015 and June 2020 were retrospectively evaluated from the Israeli Ministry of Health database. The rate of CMA with clinically significant (pathogenic or likely pathogenic) findings was calculated and compared to a local Israeli cohort of 5,541 pregnancies with normal ultrasound.
Background: Evidence comparing the yield of chromosomal microarray analysis to noninvasive prenatal screening in pregnancies with congenital heart anomalies is currently limited.
Objective: This study aimed to examine the residual risk of clinically significant chromosomal microarray analysis results in fetuses with congenital heart defects by its various subtypes following a normal noninvasive prenatal screening.
Study Design: Using a population-based, countrywide computerized database, we retrieved the reports of all pregnancies undergoing chromosomal microarray analysis because of congenital heart defects through the years 2013-2019.
This study aimed to examine the implications of reporting heterozygous losses of recessive genes in Chromosomal Microarray Analysis (CMA), based on the incidence of microdeletions of three common hearing impairment genes in the local cohort and the prevalence of sequence variants in these genes in worldwide databases. Prevalence of heterozygous microdeletions in OTOA and STRC genes, as well as deletions in the DFNB1 locus encompassing GJB6 gene, was determined using electronic database of Rabin Medical Center. ClinVar archive and Deafness Variation Database were used to generate a list of clinically significant sequence variants in these three genes, as well as GJB2 gene, and estimation of the frequency of sequence variants was performed.
View Article and Find Full Text PDFDiagnosis of rare copy number variants (CNVs) with scarce literature evidence poses a major challenge for interpretation of the clinical significance of chromosomal microarray analysis (CMA) results, especially in the prenatal setting. Bioinformatic tools can be used to assist in this issue; however, this prediction can be imprecise. Our objective was to describe the phenotype of the rare copy number losses encompassing the 8q24.
View Article and Find Full Text PDFPurpose: To analyze the risk for clinically significant microarray aberrations in pregnancies with polyhydramnios.
Methods: Data from all chromosomal microarray analyses (CMA) performed due to polyhydramnios between January 2013 and December 2019 were retrospectively obtained from the Ministry of Health Database. The rate of clinically significant (pathogenic and likely pathogenic) CMA findings in isolated and non-isolated polyhydramnios cohorts was compared to a local control group of 5541 fetuses with normal ultrasound, in which 78 (1.
Introduction: We evaluated the yield of chromosomal microarray analysis in pregnancies complicated with fetal growth restriction (FGR) according to specific clinical parameters.
Methods: The study was based on national records from the Israeli Ministry of Health. Chromosomal microarray analyses of amniocenteses performed nationwide for the indication of FGR, from January 2016 to March 2018, were included.