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American Journal of Medical Genetics.... Mar 2020Congenital heart disease (CHD) remains the most common birth defect, with an estimated incidence of approximately 1% of all births. The population of adults with CHD is... (Review)
Review
Congenital heart disease (CHD) remains the most common birth defect, with an estimated incidence of approximately 1% of all births. The population of adults with CHD is growing rapidly with advances in medical care. Overall survival to adulthood in the current era estimated to exceed 90%. Genetic causes of CHD can be classified into several broad categories: (a) chromosomal aneuploidy, (b) large chromosomal deletion or duplication, (c) single gene mutation, and (d) copy number variation. However, only 20-30% of CHD cases have an established etiology characterized by either genetic abnormalities or environmental factors. The role of genetics in the field of adult CHD is only increasing. More adult patients with CHD are seeking genetic counseling to understand the etiology of their underlying CHD and the risks to future offspring. A multidisciplinary approach is essential to provide appropriate counseling to patients regarding indications for genetic testing and interpretations of results. Novel advances with precision medicine may soon enable clinicians to individualize therapies for a comprehensive approach to the care of adult patients with CHD.
Topics: Adult; Aneuploidy; Chromosome Deletion; Chromosome Duplication; Congenital Abnormalities; DNA Copy Number Variations; Genetic Diseases, Inborn; Genetic Testing; Heart Defects, Congenital; Humans
PubMed: 32052945
DOI: 10.1002/ajmg.c.31777 -
BMJ Case Reports Mar 2023Genetic conditions have varied presentations, and one of them is the association with multiple malformation syndrome (MMS), which has a high mortality rate in the...
Genetic conditions have varied presentations, and one of them is the association with multiple malformation syndrome (MMS), which has a high mortality rate in the immediate postnatal period. Here, we describe a neonate born with multiple anomalies-wide anterior and posterior fontanelle, metopic suture, flat nasal bridge, hypertelorism, low set dysplastic ears, corneal cloudiness, micrognathia, webbed neck, simian crease, undescended testis, hypospadias, congenital talipes equinovarus, hypoplastic inferior cerebellar vermis, poor reflexes, hypotonia and ventricular septal defect. There was a history of sibling death with similar malformations, pointing towards a genetic aetiology. Clinical exome sequencing yielded the diagnosis of Zellweger syndrome with a rare mutation in gene. Inherited metabolic syndromes frequently masquerade as malformations, but family history of an affected sibling and clinical suspicion aided diagnosis of the infant.
Topics: Infant; Infant, Newborn; Male; Humans; Zellweger Syndrome; Heart Septal Defects, Ventricular; Abnormalities, Multiple; Mutation; Clubfoot
PubMed: 36931687
DOI: 10.1136/bcr-2022-252014 -
European Journal of Medical Genetics Jan 2020Our objective was to review the phenotypic and genetic characteristics of tetrasomy 5p from the fetal period until adulthood including prenatal diagnostic evaluations. (Review)
Review
OBJECTIVE
Our objective was to review the phenotypic and genetic characteristics of tetrasomy 5p from the fetal period until adulthood including prenatal diagnostic evaluations.
BACKGROUND
Tetrasomy 5p is a rare chromosomal abnormality. Of the 14 reports, most document mosaic tetrasomy 5p resulting from a supernumerary marker chromosome or isochromosome. There is a wide range of phenotypic manifestations with severity related to more proximal breakpoints and the degree of mosaicism.
DESIGN
We conducted a systematic review using Scopus, PubMed Central® and Ovid MEDLINE® from inception through July 1, 2018 for all articles describing tetrasomy 5p. All articles describing the syndrome of tetrasomy 5p were included.
RESULTS
Of the 15 included cases, 13 exhibited mosaic tetrasomy and two had complete tetrasomy identified by amniocentesis. The most common features include seizures (8/11 live births, 73%), hypotonia (7/11 live births, 64%), developmental delay (7/9 cases that reached childhood, 78%), abnormal external ears (6/11 live births, 55%), short stature (6/11 live births, 55%), ventriculomegaly (5/11 live births, 45.5%) and congenital heart defect (6/15 cases, 40%). The clinical phenotype ranged in severity from mild with no defining characteristics to severe with seizures, developmental delay, and multiple congenital anomalies, resulting in early death. Of these 15 cases, only 6 were diagnosed prenatally by prenatal genetic testing (40%) with prenatal ultrasound identifying abnormalities in 4/6 (67%). Confined placental mosaicism (CPM) was diagnosed in six additional cases due to discordance between CVS and amniocentesis results. Four of the five live births returned for evaluation and each showed normal development.
CONCLUSIONS
Fourteen out of 15 (93%) cases of tetrasomy 5p were associated with an abnormal phenotype. Once a diagnosis is made prenatally, a detailed anatomy ultrasound and fetal echocardiogram must be performed to further characterize any structural abnormalities of the fetus and potentially estimate the clinical severity. Caution should be exercised when prenatal diagnosis of mosaic tetrasomy 5p is found by chorionic villus sampling. CVS alone is insufficient to diagnose tetrasomy 5p and needs to be confirmed with amniocentesis. Our review seeks to inform clinicians on the current literature regarding tetrasomy 5p so that they may better counsel patients when this syndrome is diagnosed.
Topics: Abnormalities, Multiple; Adult; Amniocentesis; Child; Chromosome Disorders; Chromosomes, Human, Pair 5; Developmental Disabilities; Female; Genetic Testing; Humans; In Situ Hybridization, Fluorescence; Isochromosomes; Karyotyping; Male; Mosaicism; Pregnancy; Prenatal Diagnosis; Tetrasomy
PubMed: 30797979
DOI: 10.1016/j.ejmg.2019.02.006 -
Biochemical Society Transactions Jun 2021The Eyes Absent (EYA) transactivator-phosphatase proteins are important contributors to cell-fate determination processes and to the development of multiple organs. The... (Review)
Review
The Eyes Absent (EYA) transactivator-phosphatase proteins are important contributors to cell-fate determination processes and to the development of multiple organs. The transcriptional regulatory activity as well as the protein tyrosine phosphatase activities of the EYA proteins can independently contribute to proliferation, differentiation, morphogenesis and tissue homeostasis in different contexts. Aberrant EYA levels or activity are associated with numerous syndromic and non-syndromic developmental disorders, as well as cancers. Commensurate with the multiplicity of biochemical activities carried out by the EYA proteins, they impact upon a range of cellular signaling pathways. Here, we provide a broad overview of the roles played by EYA proteins in development, and highlight the molecular signaling pathways known to be linked with EYA-associated organ development and developmental disorders.
Topics: Animals; Congenital Abnormalities; Eye; Gene Expression Regulation, Developmental; Genetic Predisposition to Disease; Humans; Kidney; Mutation; Protein Tyrosine Phosphatases; Trans-Activators
PubMed: 34196366
DOI: 10.1042/BST20201302 -
Fertility and Sterility Aug 2020Male factor infertility is a significant problem present in up to 50% of infertile couples. The relationship between male infertility and systemic disease is of... (Review)
Review
Male factor infertility is a significant problem present in up to 50% of infertile couples. The relationship between male infertility and systemic disease is of significant interest, and emerging evidence suggests a relationship between male infertility and male genitourinary (GU) birth defects (cryptorchidism, hypospadias, ambiguous genitalia, and congenital anomalies of the kidney and urinary tract). Many of these birth defects are treated in isolation by busy urologists without acknowledgment that these may be related to more global syndromic conditions. Conversely, geneticists and nonurologists who treat variable systemic phenotypes may overlook GU defects, which are indeed related conditions. Many of these defects are attributed to copy number variants dosage-sensitive genes due to chromosome microdeletions or microduplications. These variants are responsible for disease phenotypes seen in the general population. The copy number variants described in this review are syndromic in some cases and responsible for both GU birth defects as well as other systemic phenotypes. This review highlights the emerging evidence between these birth defects, male infertility, and other systemic conditions.
Topics: Chromosome Deletion; Chromosome Duplication; DNA Copy Number Variations; Fertility; Gene Dosage; Genetic Predisposition to Disease; Humans; Infertility, Male; Male; Mutation; Phenotype; Risk Assessment; Risk Factors; Urogenital Abnormalities
PubMed: 32741459
DOI: 10.1016/j.fertnstert.2020.06.042 -
European Journal of Medical Genetics Mar 2021Mayer-Rokitansky-Küster-Hauser (MRKH) Syndrome is a sex development disorder that affects 1 in every 4500 46, XX live births. At least a subset of MRKH syndrome is... (Review)
Review
Mayer-Rokitansky-Küster-Hauser (MRKH) Syndrome is a sex development disorder that affects 1 in every 4500 46, XX live births. At least a subset of MRKH syndrome is genetically related to which various candidate genes have been identified. The growth regulation by estrogen in breast cancer 1-like gene (GREB1L) is an androgen-regulated gene reported to be a co-activator of the retinoic acid receptor gene (RAR). Thus expression levels of GREB1L have implications on renal system cellular differentiation, morphogenesis, and homeostasis in vertebrates. Variants of GREB1L have been reported in familial and sporadic MRKH Syndrome and more importantly, in a three-generation family ofMRKH syndrome propositae. Much the same way, Mutants of GREB1L have also been identified in isolated bilateral renal agenesis and deafness both of which are extra-genital tract anomalies in MRKH type 2. Again, renal agenesis transgenic mice have been produced from an E13.5 CRISPR/cas9 GREB1L mutagenesis. Though no GREB1L mutation has been reported in cardiac malformation, there is evidence that GREB1L is involved in ventricular development. Here, we intorigate evidence that projects GREB1L as a candidate gene of Mayer-Rokitansky-Küster-Hauser Syndrome and propose that functional validation analysis to that effect is imparative.
Topics: 46, XX Disorders of Sex Development; Animals; Congenital Abnormalities; Humans; Mullerian Ducts; Mutation; Neoplasm Proteins; Phenotype
PubMed: 33548512
DOI: 10.1016/j.ejmg.2021.104158 -
Veterinary Pathology Mar 2020Bicuspid aortic valve (BAV) is the most common human congenital cardiac malformation. Although the etiology is unknown for most patients, formation of the 2 main BAV... (Review)
Review
Bicuspid aortic valve (BAV) is the most common human congenital cardiac malformation. Although the etiology is unknown for most patients, formation of the 2 main BAV anatomic types (A and B) has been shown to rely on distinct morphogenetic mechanisms. Animal models of BAV include 2 spontaneous hamster strains and 27 genetically modified mouse strains. To assess the value of these models for extrapolation to humans, we examined the aortic valve anatomy of 4340 hamsters and 1823 mice from 8 and 7 unmodified strains, respectively. In addition, we reviewed the literature describing BAV in nonhuman mammals. The incidences of BAV types A and B were 2.3% and 0.03% in control hamsters and 0% and 0.3% in control mice, respectively. Hamsters from the spontaneous model had BAV type A only, whereas mice from 2 of 27 genetically modified strains had BAV type A, 23 of 27 had BAV type B, and 2 of 27 had both BAV types. In both species, BAV incidence was dependent on genetic background. Unlike mice, hamsters had a wide spectrum of aortic valve morphologies. We showed interspecific differences in the occurrence of BAV between humans, hamsters, and mice that should be considered when studying aortic valve disease using animal models. Our results suggest that genetic modifiers play a significant role in both the morphology and incidence of BAV. We propose that mutations causing anomalies in specific cardiac morphogenetic processes or cell lineages may lead to BAV types A, B, or both, depending on additional genetic, environmental, and epigenetic factors.
Topics: Animals; Aortic Valve; Bicuspid Aortic Valve Disease; Cricetinae; Disease Models, Animal; Humans; Incidence; Mice; Mutation; Retrospective Studies
PubMed: 32079504
DOI: 10.1177/0300985819900018 -
The Journal of Craniofacial SurgeryThe symptoms associated with microtia are ever-changing and not to stick to 1 pattern. The symptoms associated with microtia are constantly changing and are not set in...
OBJECTIVES
The symptoms associated with microtia are ever-changing and not to stick to 1 pattern. The symptoms associated with microtia are constantly changing and are not set in stone. The aim of this article was to describe the various phenotypes from multiple systems found in microtitis patients included in the DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources database, and to analyze possible pathogenic mutations.
METHODS
DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources is an interactive web-based database, which incorporates a suite of tools designed to aid the interpretation of genomic variants. The term "microtia" was used as the search term, and the data extracted from the DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources for this study was updated until October 2020. Pearson chi-squared test was used to test associations between types of genomic variants and the pathogenicity of variants.
RESULTS
Of the 386 cases enrolled in the study, 99% (n = 382) had 1 or more associated abnormalities. The most frequently detected abnormalities were those of the face and neck (n = 362 [93.8% of all cases]); musculoskeletal system (n = 337 [87.3%]); and nervous system (n = 334 [86.5%]), followed by abnormalities of limbs (n = 252 [65.3%]); the eye (n = 212 [54.9%]); and the integument (n = 200 [51.8%]). Besides, a total of 479 genomic variants were determined, including sequence variants and copy number variants (loss and gain). The pathogenicity of loss-type variants was significantly higher among other types (P < 0.001). Twelve sharing variants had more than 5 repeats, and the repeated fragments were concentrated on chromosome 3, 7, 9, 10, 11, 15, 17, 18, and 22.
CONCLUSIONS
Identification of the relation between phenotypes and genotypes will facilitate the uncovering of the mechanism of microtia and the study of potential therapeutic targets.
Topics: Congenital Microtia; DNA Copy Number Variations; Genotype; Humans; Mutation; Phenotype
PubMed: 34310428
DOI: 10.1097/SCS.0000000000008037 -
BMC Medical Genomics Oct 2023Whole-exome sequencing (WES) significantly improves the diagnosis of the etiology of fetal structural anomalies. This study aims to evaluate the diagnostic value of...
BACKGROUND
Whole-exome sequencing (WES) significantly improves the diagnosis of the etiology of fetal structural anomalies. This study aims to evaluate the diagnostic value of prenatal WES and to investigate the pathogenic variants in structurally abnormal fetuses.
METHODS
We recruited 144 fetuses with structural anomalies between 14 and 2020 and 15 December 2021 in the study. Genetic screening was performed by WES combined with karyotyping and chromosomal microarray analysis. The molecular diagnostic yield of prenatal WES for each type of fetal structural anomaly and the identified pathogenic genes and mutations were reported.
RESULTS
In this study, we retrospectively analyzed the clinical and genetic data of 145 structurally anomalous fetuses. These cases were classified into 9 phenotypic classes based on antenatal ultrasound findings. Thirty-eight pathogenic variants in 24 genes were identified in 35 of the 145 cases, including 14 novel variants in 13 genes (EP300, MYH3, TSC2, MMP9, CPLANE1, INVS, COL1A1, EYA1, TTC21B, MKS1, COL11A2, PDHA1 and L1CAM). Five additional pathogenic variants were classified as incidental findings. Our study showed that the overall diagnosis rate of WES was 28.1% (27/96) in the parent-fetus trio cases and 16.3% (8/49) in the proband-only cases. Fetuses with musculoskeletal anomalies had the highest diagnostic yield (51.4%, 19/37). In addition, FGFR3 and COL1A1 were the most common pathogenic genes.
CONCLUSIONS
Our work expands the mutation spectrum of the genes associated with fetal structural anomalies and provides valuable information for future parental genetic counselling and pregnancy management of the structurally anomalous fetuses.
Topics: Female; Humans; Pregnancy; East Asian People; Exome Sequencing; Fetus; Pregnancy Trimester, First; Prenatal Diagnosis; Retrospective Studies; Ultrasonography, Prenatal; Congenital Abnormalities
PubMed: 37880672
DOI: 10.1186/s12920-023-01697-3 -
International Journal of Molecular... Dec 2023Infertility affects around 1 in 5 couples in the world. Congenital absence of the uterus results in absolute infertility in females. Müllerian agenesis is the... (Review)
Review
Infertility affects around 1 in 5 couples in the world. Congenital absence of the uterus results in absolute infertility in females. Müllerian agenesis is the nondevelopment of the uterus. Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a condition of uterovaginal agenesis in the presence of normal ovaries and the 46 XX Karyotype. With advancements in reproductive techniques, women with MA having biological offspring is possible. The exact etiology of MA is unknown, although several genes and mechanisms affect the development of Müllerian ducts. Through this systematic review of the available literature, we searched for the genetic basis of MA. The aims included identification of the genes, chromosomal locations, changes responsible for MA, and fertility options, in order to offer proper management and counseling to these women with MA. A total of 85 studies were identified through searches. Most of the studies identified multiple genes at various locations, although the commonest involved chromosomes 1, 17, and 22. There is also conflicting evidence of the involvement of various candidate genes in the studies. The etiology of MA seems to be multifactorial and complex, involving multiple genes and mechanisms including various mutations and mosaicism.
Topics: Humans; Female; Mullerian Ducts; Infertility; 46, XX Disorders of Sex Development; Mosaicism; Congenital Abnormalities
PubMed: 38203291
DOI: 10.3390/ijms25010120