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Genes Oct 2021Biallelic truncating variants result in cilia dysfunction and have been reported in four infants with Joubert syndrome and orofaciodigital syndrome type VI,...
Biallelic truncating variants result in cilia dysfunction and have been reported in four infants with Joubert syndrome and orofaciodigital syndrome type VI, respectively. We report here on three adult siblings, 18 to 40 years of age, homozygous for the known c.354_357delinsCACTC (p.Gln118Hisfs*20) variant. Detailed clinical examinations were performed including ocular and gait analyses, skeletal- and neuroimaging. All three patients presented with neurological and oculomotor symptoms since birth and mild skeletal dysplasia in infancy resulting in characteristic gait abnormalities. We document mild skeletal dysplasia, abnormal gait with increased hip rotation and increased external foot rotation, ataxia, variable polydactyly, ocular Duane syndrome, progressive ophthalmoplegia, nystagmus, situs inversus of the retinal vessels, olfactory bulb aplasia, and corpus callosal dysgenesis as novel features in -ciliopathy. We show that intellectual disability is mild to moderate and retinal, renal and liver function is normal in these affected adults. Our study thus expands the -related Joubert syndrome to a mainly neurological and skeletal ciliopathy phenotype with predominant oculomotor dysfunction but otherwise stable outcome in adults. Diagnosis of -related disorder was impeded by segregation of multiple neurogenetic disorders in the same family, highlighting the importance of extended clinical and genetic studies in families with complex phenotypes.
Topics: Abnormalities, Multiple; Adolescent; Adult; Cerebellum; Ciliopathies; Consanguinity; Cytoskeletal Proteins; Duane Retraction Syndrome; Eye Abnormalities; Female; Humans; Kidney Diseases, Cystic; Male; Nervous System Malformations; Phenotype; Retina; Saudi Arabia; Siblings; Young Adult
PubMed: 34828254
DOI: 10.3390/genes12111648 -
Scientific Reports Oct 2020Duane retraction syndrome (DRS) is a neuromuscular dysfunction of the eyes. Although many causative genes of DRS have been identified in Europe and the United States,...
Duane retraction syndrome (DRS) is a neuromuscular dysfunction of the eyes. Although many causative genes of DRS have been identified in Europe and the United States, few reports have been published in regard to Chinese DRS. The aim of the present study was to explore the genetic defect of DRS in a Chinese family. Exome sequencing was used to identify the disease-causing gene for the two affected family members. Ophthalmic and physical examinations, as well as genetic screenings for variants in chimerin 1 (CHN1), were performed for all family members. Functional analyses of a CHN1 variant in 293T cells included a Rac-GTP activation assay, α2-chimaerin translocation assay, and co-immunoprecipitation assay. Genetic analysis revealed a NM_001822.7: c.637T > G variant in the CHN1 gene, which resulted in the substitution of a highly conserved C1 domain with valine at codon 213 (NP_001813.1: p.(Phe213Val)) (ClinVar Accession Number: SCV001335305). In-silico analysis revealed that the p.(Phe213Val) substitution affected the protein stability and connections among the amino acids of CHN1 in terms of its tertiary protein structure. Functional studies indicated that the p.(Phe213Val) substitution reduced Rac-GTP activity and enhanced membrane translocation in response to phorbol-myristoyl acetate (PMA). Together with previous studies, our present findings demonstrate that CHN1 may be an important causative gene for different ethnicities with DRS.
Topics: Adolescent; Adult; Asian People; Child; Chimerin 1; Duane Retraction Syndrome; Family; Female; Humans; Male; Middle Aged; Mutation, Missense; Pedigree; Young Adult
PubMed: 33004823
DOI: 10.1038/s41598-020-73190-1 -
Saudi Journal of Ophthalmology :... 2021Consecutive exotropia is considered as a rare complication after medial rectus recession that is performed for cases of esotropic Duane syndrome. Here, we present a case...
Consecutive exotropia is considered as a rare complication after medial rectus recession that is performed for cases of esotropic Duane syndrome. Here, we present a case of 5-year-old female initially presented with the limitation of abduction, narrowing of the palpebral fissure, and globe retraction of the left eye along with a mild left face turn. She was diagnosed with Duane syndrome Type 1. She was treated with the medial rectus recession (6.5 mm). Postsurgery, she developed a consecutive exotropia. This was managed successfully with the ipsilateral lateral rectus recession (8 mm). Following this surgery, the patient was orthoptic in the primary position and her abnormal head posture was markedly improved.
PubMed: 35391814
DOI: 10.4103/1319-4534.337851 -
Structure of SALL4 zinc finger domain reveals link between AT-rich DNA binding and Okihiro syndrome.Life Science Alliance Mar 2023Spalt-like 4 (SALL4) maintains vertebrate embryonic stem cell identity and is required for the development of multiple organs, including limbs. Mutations in SALL4 are...
Spalt-like 4 (SALL4) maintains vertebrate embryonic stem cell identity and is required for the development of multiple organs, including limbs. Mutations in SALL4 are associated with Okihiro syndrome, and SALL4 is also a known target of thalidomide. SALL4 protein has a distinct preference for AT-rich sequences, recognised by a pair of zinc fingers at the C-terminus. However, unlike many characterised zinc finger proteins, SALL4 shows flexible recognition with many different combinations of AT-rich sequences being targeted. SALL4 interacts with the NuRD corepressor complex which potentially mediates repression of AT-rich genes. We present a crystal structure of SALL4 C-terminal zinc fingers with an AT-rich DNA sequence, which shows that SALL4 uses small hydrophobic and polar side chains to provide flexible recognition in the major groove. Missense mutations reported in patients that lie within the C-terminal zinc fingers reduced overall binding to DNA but not the preference for AT-rich sequences. Furthermore, these mutations altered association of SALL4 with AT-rich genomic sites, providing evidence that these mutations are likely pathogenic.
Topics: Humans; Duane Retraction Syndrome; Mutation; Transcription Factors; Zinc Fingers
PubMed: 36635047
DOI: 10.26508/lsa.202201588 -
Oman Journal of Ophthalmology 2023Achondroplasia is an autosomal dominant congenital disorder of endochondral ossification, induced by abnormal activity of fibroblast growth factor receptor 3. Affected...
Achondroplasia is an autosomal dominant congenital disorder of endochondral ossification, induced by abnormal activity of fibroblast growth factor receptor 3. Affected individuals have short stature and often present with neurological and skeletal complications. Most have normal intelligence. Ocular association with achondroplasia include simple microphthalmos, congenital-onset glaucoma with presumed Axenfeld-Rieger anomaly, telecanthus, exotropia, inferior oblique overaction, angle anomalies, Duane retraction syndrome, cone-rod dystrophy, fundus albipunctatus, chorioretinal coloboma, macular coloboma, keratoconus, and developmental cataract. A 6-year-old achondroplasia boy with developmental delay had a high axial length (high myopia) in both eyes. This child had a left eye subluxated cataractous lens, while the other eye showed mild lens changes. All achondroplasia patients should be routinely screened in detail for lens and other ophthalmological anomalies so that they can undergo timely intervention and management.
PubMed: 38059098
DOI: 10.4103/ojo.ojo_42_23 -
Scientific Reports Aug 2019Thalidomide is widely used for several diseases; however, it causes malformations in embryos exposed during pregnancy. The complete understanding of the mechanisms by...
Thalidomide is widely used for several diseases; however, it causes malformations in embryos exposed during pregnancy. The complete understanding of the mechanisms by which thalidomide affects the embryo development has not yet been obtained. The phenotypic similarity makes TE a phenocopy of syndromes caused by mutations in ESCO2, SALL4 and TBX5 genes. Recently, SALL4 and TBX5 were demonstrated to be thalidomide targets. To understand if these genes act in the TE development, we sequenced them in 27 individuals with TE; we verified how thalidomide affect them in human pluripotent stem cells (hPSCs) through a differential gene expression (DGE) analysis from GSE63935; and we evaluated how these genes are functionally related through an interaction network analysis. We identified 8 variants in ESCO2, 15 in SALL4 and 15 in TBX5. We compared allelic frequencies with data from ExAC, 1000 Genomes and ABraOM databases; eight variants were significantly different (p < 0.05). Eleven variants in SALL4 and TBX5 were previously associated with cardiac diseases or malformations; however, in TE sample there was no association. Variant effect prediction tools showed 97% of the variants with potential to influence in these genes regulation. DGE analysis showed a significant reduction of ESCO2 in hPSCs after thalidomide exposure.
Topics: Abnormalities, Multiple; Acetyltransferases; Brazil; Cell Line; Chromosomal Proteins, Non-Histone; Craniofacial Abnormalities; Datasets as Topic; Duane Retraction Syndrome; Ectromelia; Female; Gene Expression Profiling; Gene Frequency; Genetic Predisposition to Disease; Heart Defects, Congenital; Heart Septal Defects, Atrial; Humans; Hypertelorism; Leprosy; Lower Extremity Deformities, Congenital; Male; Mutation; Pluripotent Stem Cells; Polymorphism, Single Nucleotide; Pregnancy; Pregnancy Complications; Protein Interaction Maps; T-Box Domain Proteins; Teratogenesis; Thalidomide; Transcription Factors; Upper Extremity Deformities, Congenital
PubMed: 31388035
DOI: 10.1038/s41598-019-47739-8 -
BMC Medical Genomics Feb 2023SALL4, a member of the SALL genes family, encodes a zinc-finger transcriptional factor that either activates or represses gene transcription depending on cell type...
BACKGROUND
SALL4, a member of the SALL genes family, encodes a zinc-finger transcriptional factor that either activates or represses gene transcription depending on cell type during embryonic development. SALL4 mutations cause extremely variable conditions including Duane-radial ray (DRR), Okihiro, Holt-oram, Acro-renal ocular and IVIC syndromes, all with autosomal dominant inheritance pattern. However, all these syndromes with different terminologies are actually the same entity termed SALL4 related disorders.
CASE PRESENTATION
Herein, we examine an Iranian patient suspected to DRR syndrome which has not been previously described in the population. Whole-exome sequencing (WES) was performed to examine pathogenic genes in the proband. Subsequently, Sanger sequencing was used to confirm the mutation found. To elucidate the effects of the identified mutation, clinical data of patient was collected. Morever, the possible impact of the mutation found on the corresponding protein was evaluated using bioinformatics tools. WES identifed a novel de novo heterozygous nonsense mutation in exon 2 of SALL4 gene (c.712 C > T:p.Q238X). Subsequently, segregation and phenotype-genotype correlation analysis as well as in-silico approaches confirmed the autosomal dominance inheritance and disease-causing nature of the identified mutation. In addition, studied patient had features not described previously, including kyphoscoliosis, dimple presacral sinus, barrel chest and artric disc (C6-C7). These manifestations could be additional characteristics of the growing phenotypic spectrum of SALL4 related disorders.
CONCLUSION
Our findings could extend the pathogenic mutations and phenotypic spectrum of SALL4 related disorders. Such reports can also aid to conduct genetic counseling, prenatal diagnosis and clinical management for individuals at high risk of SALL4 related disorders.
Topics: Humans; Duane Retraction Syndrome; Codon, Nonsense; Iran; Transcription Factors; Mutation; Pedigree
PubMed: 36829172
DOI: 10.1186/s12920-023-01467-1 -
Hormone Research in Paediatrics 2024The SALL4 gene encodes a transcription factor that is essential for early embryonic cellular differentiation of the epiblast and primitive endoderm. It is required for...
INTRODUCTION
The SALL4 gene encodes a transcription factor that is essential for early embryonic cellular differentiation of the epiblast and primitive endoderm. It is required for the development of neural tissue, kidney, heart, and limbs. Pathogenic SALL4 variants cause Duane-radial ray syndrome (Okihiro syndrome), acro-renal-ocular syndrome, and Holt-Oram syndrome. We report a family with vertical transmission of a SALL4 pathogenic variant leading to radial hypoplasia and kidney dystopia in several generations with additional growth hormone deficiency (GHD) in the proband.
CASE PRESENTATION
Our male proband was born at the 39th week of gestation. He was born small for gestational age (SGA; birth weight 2,550 g, -2.2 SDS; length 47 cm, -2.0 SDS). He had bilateral asymmetrical radial ray malformation (consisting of radial hypoplasia, ulnar flexure, and bilateral aplasia of the thumb) and pelvic kidney dystopia, but no cardiac malformations, clubfoot, ocular coloboma, or Duane anomaly. He was examined for progressive short stature at the age of 3.9 years, where his IGF-1 was 68 μg/L (-1.0 SD), and growth hormone (GH) after stimulation 6.2 μg/L. Other pituitary hormones were normal. A brain CT revealed normal morphology of the cerebral midline and the pituitary. He had a dental anomaly - a central mandibular ectopic canine. MRI could not be done due to the presence of metal after multiple corrective plastic surgeries of his hands. His mother's and father's heights are 152.3 cm (-2.4 SD) and 177.8 cm (-0.4 SD), respectively. His father has a milder malformation of the forearm. The affected paternal grandfather (height 164 cm; -2.3 SD) has a radial ray defect with missing opposition of the thumb. The family reports a similar phenotype of radial dysplasia in the paternal grandfather's mother. The proband started GH therapy at age 6.5 years when his height was 109 cm (-2.8 SDS) and he experienced catch-up growth as expected in GHD. Puberty started spontaneously at the age of 12.5 years. At age 13, his height was 158.7 cm (-0.2 SDS). Whole-exome sequencing revealed a nonsense variant in the SALL4 gene c.1717C>T (p.Arg573Ter) in the proband, his father, and paternal grandfather.
CONCLUSION
This is the first observation of a patient with a congenital upper limb defect due to a pathogenic SALL4 variant who has isolated GHD with no apparent cerebral or facial midline anomaly and has been successfully treated with growth hormone.
Topics: Child, Preschool; Humans; Male; Duane Retraction Syndrome; Human Growth Hormone; Hypopituitarism; Kidney; Phenotype; Transcription Factors; Upper Extremity; Adult
PubMed: 37611564
DOI: 10.1159/000531996 -
Cureus Jun 2023The levator palpebrae superioris is the primary muscle responsible for elevation of the eyelid. This muscle is innervated by the third intracranial nerve. Any pathology...
The levator palpebrae superioris is the primary muscle responsible for elevation of the eyelid. This muscle is innervated by the third intracranial nerve. Any pathology affecting the muscle or the supplying nerve can lead to blepharoptosis. In this study, we share our experience of a two-year-old baby boy patient who presented with a rare congenital disorder manifested as blepharoptosis increased with adduction bilaterally with no limitation of ocular muscles action except bilateral underaction of inferior oblique muscles. To our knowledge, this unusual presentation has not been previously reported in the literature. We aim in this report to build more knowledge on such a rare clinical presentation. Based on the findings, this could be a case of congenital innervation dysgenesis syndrome (CID)/congenital cranial dysinnervation disorders (CCDDs). CCDDs/CID is a group of conditions that includes blepharoptosis as part of their clinical presentation. This group of conditions includes Duane's retraction syndrome, congenital fibrosis of extraocular muscles, and monocular elevation defect.
PubMed: 37456445
DOI: 10.7759/cureus.40422 -
Indian Journal of Ophthalmology Jul 2020A 10-year-old boy with unilateral cryptorchidism and renal aplasia displayed features of unilateral congenital pupil sparing third cranial nerve palsy with exotropia...
A 10-year-old boy with unilateral cryptorchidism and renal aplasia displayed features of unilateral congenital pupil sparing third cranial nerve palsy with exotropia manifesting novel dysinnervation encompassing synergistic divergence with upshoot, convergence on attempted upgaze, gaze-evoked phasic conjugate torsion, and gaze-evoked nystagmus. Congenital third nucleus/nerve hypoplasia with secondary dysinnervation is classfied as congenital cranial dysinnervation disorder (CCDD). It is speculated that miswiring between prenuclear structures, otolithic pathways, interstitial nucleus of Cajal (INC), nucleus prepositus hypoglossi, and third and sixth nerve nuclei likely resulted in this novel dysinnervation. Cryptorchidism and renal aplasia if seen may point towards an overlapping phenotype with Duane-radial ray syndrome and acro-renal-ocular/IVIC syndromes.
Topics: Child; Duane Retraction Syndrome; Humans; Male; Oculomotor Muscles; Oculomotor Nerve; Oculomotor Nerve Diseases; Paralysis
PubMed: 32587205
DOI: 10.4103/ijo.IJO_1627_19