Compound heterozygous variants in MAPK8IP3 were detected in severe congenital hypotonia mimicking lethal spinal muscular atrophy.

Mitogen-activated protein kinase 8-interacting protein 3 gene (MAPK8IP3) encodes the c-Jun-amino-terminal kinase-interacting protein 3 (JIP3) and is involved in retrograde axonal transport. Heterozygous de novo pathogenic variants in MAPK8IP3 result in a neurodevelopmental disorder with or without brain abnormalities and possible axonal peripheral neuropathy. Whole-exome sequencing was performed on an individual presenting with severe congenital muscle hypotonia of neuronal origin mimicking lethal spinal muscular atrophy. Compound heterozygous rare variants (a splice and a missense) were detected in MAPK8IP3, inherited from the healthy parents. Western blot analysis in a muscle biopsy sample showed a more than 60% decrease in JIP3 expression. Here, we suggest a novel autosomal recessive phenotype of a lower motor neuron disease caused by JIP3 deficiency.

Missense MED12 variants in 22 males with intellectual disability: From nonspecific symptoms to complete syndromes.

We describe the phenotype of 22 male patients (20 probands) carrying a hemizygous missense variant in MED12. The phenotypic spectrum is very broad ranging from nonspecific intellectual disability (ID) to the three well-known syndromes: Opitz-Kaveggia syndrome, Lujan-Fryns syndrome, or Ohdo syndrome. The identified variants were randomly distributed throughout the gene (p = 0.993, χ2 test), but mostly outside the functional domains (p = 0.004; χ2 test). Statistical analyses did not show a correlation between the MED12-related phenotypes and the locations of the variants (p = 0.295; Pearson correlation), nor the protein domain involved (p = 0.422; Pearson correlation). In conclusion, establishing a genotype-phenotype correlation in MED12-related diseases remains challenging. Therefore, we think that patients with a causative MED12 variant are currently underdiagnosed due to the broad patients' clinical presentations.

Hemizygous nonsense variant in the moesin gene (MSN) leads to a new autoimmune phenotype of Immunodeficiency 50.

Here, we present the findings of an investigation involving two male siblings with juvenile total tooth loss, early-onset chronic leg ulcers, and autoimmune thyroiditis, as well as focal segmental glomerulosclerosis with associated pulmonary emphysema in one and diabetes mellitus in the other. The clinical picture and lupus anticoagulant, cryoglobulin, and cold agglutinin positivity suggested the diagnosis of antiphospholipid syndrome. Flow cytometry analysis showed immunophenotypes consistent with immune dysregulation: a low number of naive T cells, elevated CD4+ T cell counts, and decreased CD8+ T-cell counts were detected, and more than half of the T-helper population was activated. Considering the siblings' almost identical clinical phenotype, the genetic alteration was suspected in the background of the immunodeficiency. Whole exome sequencing identified a previously not described hemizygous nonsense variant (c.650G>A, p.W217X) within exon 6 of the moesin (MSN) gene localized on chromosome X, resulting in significantly decreased MSN mRNA expression compared to healthy controls. We present a putative new autoimmune phenotype of Immunodeficiency 50 (MIM300988) characterized by antiphospholipid syndrome, Hashimoto's thyroiditis, leg ulcers, and juvenile tooth loss, associated with W217X mutation of the MSN gene.

Case Report: Expressive Speech Disorder in a Family as a Hallmark of 7q31 Deletion Involving the FOXP2 Gene.

Pathogenic variants of FOXP2 gene were identified first as a monogenic cause of childhood apraxia of speech (CAS), a complex disease that is associated with an impairment of the precision and consistency of movements underlying speech, due to deficits in speech motor planning and programming. FOXP2 variants are heterogenous; single nucleotide variants and small insertions/deletions, intragenic and large-scale deletions, as well as disruptions by structural chromosomal aberrations and uniparental disomy of chromosome 7 are the most common types of mutations. FOXP2-related speech and language disorders can be classified as "FOXP2-only," wherein intragenic mutations result in haploinsufficiency of the FOXP2 gene, or "FOXP2-plus" generated by structural genomic variants (i.e., translocation, microdeletion, etc.) and having more likely developmental and behavioral disturbances adjacent to speech and language impairment. The additional phenotypes are usually related to the disruption/deletion of multiple genes neighboring FOXP2 in the affected chromosomal region. We report the clinical and genetic findings in a family with four affected individuals having expressive speech impairment as the dominant symptom and additional mild dysmorphic features in three. A 7.87 Mb interstitial deletion of the 7q31.1q31.31 region was revealed by whole genome diagnostic microarray analysis in the proband. The FOXP2 gene deletion was confirmed by multiplex ligation-dependent probe amplification (MLPA), and all family members were screened by this targeted method. The FOXP2 deletion was detected in the mother and two siblings of the proband using MLPA. Higher resolution microarray was performed in all the affected individuals to refine the extent and breakpoints of the 7q31 deletion and to exclude other pathogenic copy number variants. To the best of our knowledge, there are only two family-studies reported to date with interstitial 7q31 deletion and showing the core phenotype of FOXP2 haploinsufficiency. Our study may contribute to a better understanding of the behavioral phenotype of FOXP2 disruptions and aid in the identification of such patients. We illustrate the importance of a targeted MLPA analysis suitable for the detection of FOXP2 deletion in selected cases with a specific phenotype of expressive speech disorder. The "phenotype first" and targeted diagnostic strategy can improve the diagnostic yield of speech disorders in the routine clinical practice.

The importance of the multiplex ligation-dependent probe amplification in the identification of a novel two-exon deletion of the NR5A1 gene in a patient with 46,XY differences of sex development.

Gonadal dysgenesis (GD) is a rare cause of differences of sex development (DSD) with highly variable clinical and genetic conditions. Although identification of the causative genetic alterations can offer a clearer prognosis and personalized management to patients, more than 50% of the DSD cases still do not have an accurate genetic diagnosis. NR5A1 (previously known as SF-1), is a transcriptional regulator of genes required for normal development and functional maintenance of the gonads and the adrenal glands. Nucleotide sequence variants of the NR5A1 gene have been reported in numerous patients with GD with or without adrenal failure, however, microdeletion or partial deletion in the NR5A1 gene have been described only in a few GD cases. In this case study, we present a subject with female phenotype, mild clitoromegaly, partial GD and normal adrenal function. Cytogenetic analysis revealed a 46,XY SRY + karyotype. Microarray analysis did not identify pathogenic copy number variations, nor did panel sequencing of the most common DSD genes. Subsequently, multiplex ligation-dependent probe amplification (MLPA) was performed to test for small deletion/duplication of the most frequently affected genes associated with GD. Using this method, we have identified a novel heterozygous deletion involving exons 5 and 6 of the NR5A1 gene as the cause of abnormal sexual development of the patient. This report expands our knowledge about the range and pathogenetic role of NR5A1 mutations associated with partial gonadal dysgenesis in 46,XY DSD. Furthermore, our data emphasises the indispensable role of MLPA in the diagnosis of DSD with unclear etiology.

Cardiac arrest in kearns-sayre syndrome.

The prognosis of progressive ophthalmoplegia in patients with large-scale mitochondrial DNA deletions is highly variable and almost unpredictable. The risk to develop cardiac involvement and sudden cardiac death is strikingly high, especially in patients with Kearns-Sayre syndrome (KSS). The most typical cardiac complications of the disease are conduction defects, which usually begin with left anterior fascicular block with or without right bundle branch block (RBBB), progressing sometimes rapidly to complete atrioventricular block. Other cardiac manifestations reported are first or second degree of AV block, QT prolongation, torsades de pointes ventricular tachycardia, and rarely dilated cardiomyopathy. Most frequently syncope, sometimes even sudden cardiac death, is the first clinical sign of the cardiac disease in KSS. Due to these life-threatening cardiac conditions, patients should be carefully monitored for cardiac signs and symptoms and pacemaker implantation should be suggested early to avoid sudden cardiac arrest in KSS.Here, we present two cases of KSS with life-threatening syncope due to complete atrioventricular block. To emphasize the importance of an early pacemaker implantation, we review the literature on cardiac complications in KSS in the last 20 years. In almost all of the reviewed cases, ophthalmoplegia or ptosis was present before the cardiac manifestations. In most of the cases, syncope was the first symptom of the cardiac involvement. There was no correlation between the age of the onset of the disease and the onset of cardiac manifestations.With our current report, we increase awareness for life-threatening cardiac complications in patients with KSS.

Analysis of Hungarian patients with Rett syndrome phenotype for MECP2, CDKL5 and FOXG1 gene mutations.

Rett syndrome (RTT) is characterized by a relatively specific clinical phenotype. We screened 152 individuals with RTT phenotype. A total of 22 different known MECP2 mutations were identified in 42 subjects (27.6%). Of the 22 mutations, we identified 7 (31.8%) frameshift-causing deletions, 4 (18.2%) nonsense, 10 (45.5%) missense mutations and one insertion (4.5%). The most frequent pathologic changes were: p.Thr158Met (14.2%) and p.Arg133Cys (11.9%) missense, and p.Arg255Stop (9.5%) and p.Arg294Stop (9.5%) nonsense mutations. We also detected the c.925C >T (p.Arg309Trp) mutation in an affected patient, whose role in RTT pathogenesis is still unknown. Patients without detectable MECP2 defects were screened for mutations of cyclin-dependent kinase-like 5 (CDKL5) gene, responsible for the early-onset variant of RTT. We discovered two novel mutations: c.607G >T resulting in a termination codon at aa203, disrupting the catalytic domain, and c.1708G >T leading to a stop at aa570 of the C terminus. Both patients with CDKL5 mutation presented therapy-resistant epilepsy and a phenotype fitting with the diagnosis of early-onset variant of RTT. No FOXG1 mutation was detected in any of the remaining patients. A total of 110 (72.5%) patients remained without molecular genetic diagnosis that necessitates further search for novel gene mutations in this phenotype. Our results also suggest the need of screening for CDKL5 mutations in patients with Rett phenotype tested negative for MECP2 mutations.

[Psychological aspects of presymptomatic diagnosis in Huntington disease]. / A Huntington-betegség preszimptómás genetikai vizsgálatát kérok pszichológiai felkészítése.

INTRODUCTION: Huntington disease is an autosomal dominant, progressive neurodegenerative disorder, starting in adulthood. International recommendations were created for presymptomatic testing (genetic test performed before symptoms appear). During the initial preparation for presymptomatic testing, a genetic counsellor, neurologist and psychologist attend. AIM: The authors evaluated whether the international recommendations could be used in the 10 cases examined, and how much the process must be individualized. METHOD: The authors stated a protocol based on the literature, and utilized it for the purpose of obtaining informed consent. Psychological preparation was an important part of this process. Ten cases are presented in whose families Huntington disease was determined, and therefore they asked for their own presymptomatic testing. RESULTS: From the ten persons who asked for examination, four changed their minds during the psychological process; four were attended in the process, and two asked for the test without any psychological preparation. CONCLUSION: Along with the following of the protocol steps individual factors need to be taken into account in order to ideally plan the preparation process of presymptomatic testing. Authors recommend keeping contact with the individuals after genetic testing.

[Novel approaches to the background of developmental abnormalities: clinical genetics of transcription factors]. / Uj lehetoségek a fejlodési rendellenességek hátterének feltárására: transzkripciós faktorok klinikai genetikája.

Transcription factors are highly conserved proteins with preserved structure and function for up to a hundred million years. They regulate protein formation and function by binding to DNA and controlling gene expression. Mutations are generally lethal, but can play role in endocrine disorders and tumor genesis. They are necessary for cell growth, proliferation, differentiation and are required in tissue and organ development during normal embryogenesis. Consequently, transcription factors are essential in developmental processes and homeostasis. Mutations of genes encoding transcriptional regulators have been shown to be involved in a number of various genetic diseases, in particular malformation of the skeletal system, cranium, limbs, as well as some congenital syndromes with anomalies of these organs and somatic/mental retardation. Evidences accumulate to support the need of transcription factor mutation identification in the clinical practice. The present study reviews the most important congenital malformations and genetic syndromes which are thought to be related to mutations in classic transcription factors, and in which determination of transcription factors might be of clinical significance, even in the near future, for exact causative diagnosis and genetic counseling in affected families. In addition, studies of the transcription factors may lead to a better understanding of human embryogenesis.

Transient progeroid phenotype and lipodystrophy in mosaic polyploidy.

Wiedemann-Rautenstrauch syndrome is a rare disorder with a progressive course and early lethality. Severe mental and growth retardation, muscle hypotonia, a progeroid face, wrinkled skin, relative macrocephaly with late closure of the anterior fontanel, arachnodactyly and congenital heart defects are also typical. We report on a female infant with all the characteristic features of this syndrome after birth. Chromosomal studies on peripheral leukocytes showed a normal karyotype. In view of an abnormal lipid distribution and lipodystrophy, metabolic studies for congenital disorders of glycosylation have been performed with normal results. At the age of 2 years 6 months the progeroid signs were no longer present, and the patient had a striking improvement in her psychomotor development. As there are overlapping features in Wiedemann-Rautenstrauch syndrome and in mosaic polyploidy, including psychomotor retardation, reduced peripheral muscle bulk, arachnodactyly and lipodystrophy, chromosome analysis was performed in the fibroblast culture of our patient. A mosaic triploidy/tetraploidy was detected in 60% and 14% of the cells, respectively. We therefore recommend chromosome analysis of fibroblasts from patients with a neonatal presentation of progeroid features and lipodystrophy.

Screening for CDG type Ia in Joubert syndrome.

BACKGROUND: The features of Joubert syndrome include hypotonia, ataxia, characteristic neuro-imaging findings, episodic hypoventilation, psychomotor retardation, and abnormal eye movements. Common symptoms in congenital disorders of glycosylation (CDG) type Ia are muscle hypotonia, cerebellar hypoplasia, ataxia, mental retardation, ophthalmologic involvement, failure to thrive, abnormal fat distribution, and hepatopathy. It has been postulated that some Joubert syndrome patients might have an underlying disorder of protein glycosylation. MATERIAL/METHODS: Screening for disorders of glycosylation was performed in five children diagnosed with Joubert syndrome. Data were retrospectively collected from clinical charts, the patients were reexamined by clinical geneticists, and available neuro-imaging data were also reanalyzed. Diagnoses were established based on results of serum transferrin isoelectric focusing, phosphomannomutase enzyme activity measurements, and DNA mutation analysis. RESULTS: We confirmed the diagnoses of CDG type Ia in two of the five children originally diagnosed with Joubert syndrome. The symptoms of the two syndromes were clearly distinguishable. CONCLUSIONS: Syndromic patients with congenital vermis malformations should be screened for congenital disorders of glycosylation.

[Mutational analysis of the MECP2 gene by direct sequencing in Hungarian patients with Rett syndrome]. / Az MECP2 gén mutációinak analízise direkt szekvenálással magyarországi Rett-szindrómás betegekben.

INTRODUCTION: Rett syndrome is an X-linked neurodevelopmental disorder characterized by loss of acquired skills and stereotypical hand movements. Mutations in the gene encoding methyl-CpG-binding protein 2 have been identified as cause of Rett syndrome in 1999. AIM: The authors initialized mutation screening of this gene in Hungarian patients identified on the base of clinical manifestation in various institutes. So far 25 patients were examined who were supposed to have Rett syndrome. METHOD: Total genomic DNA was extracted from peripheral blood with routine desalting method for mutation analysis. The three coding regions of the gene were amplified with primer pairs described. The PCR products were analysed by direct sequencing. RESULTS: Mutations in methyl-CpG-binding protein 2 gene were found in 17/25 cases (68%). This rate of mutation among Rett patients corresponds well with the findings of other studies. Two novel mutations were found. In the first patient whose history was characterized by a slower than normal progression, a G insertion at the base position 276 of exon 3 was detected, while in the second child a double deletion (191, and 9 bases, resp.) in exon 4 was identified.

Ulnar/fibular ray defect and brachydactyly in a family: a possible new autosomal dominant syndrome.

The ulnar-mammary syndrome (MIM 181450) includes postaxial ray defects, abnormalities of growth, delayed sexual development, and mammary and apocrine gland hypoplasia. Brachydactyly type E (MIM 113300) presents with shortening of the metacarpals and phalanges in the ulnar ray in association with moderately short stature. We describe a three-generation family with variable expression of ulnar/fibular hypoplasia, brachydactyly, ulnar ray defects and short stature. The proband had ulnar hypoplasia with missing IV-Vth fingers, fibular hypoplasia on the right, bilateral club feet, growth retardation, a hypoplastic mid-face, an ASD and hemangiomas. She had normal mammary tissue and normal sweating. The mother had short stature, midfacial hypoplasia, a hypoplastic ulna and hypoplasia of the IVth metacarpal (brachydactyly) on the right without other associated malformations. The maternal grandfather had mild bilateral fibular hypoplasia and midphalangeal brachydactyly of the IV-Vth toes. His sister had mild short stature and shortening of the IVth metacarpal of the left hand. Two-point linkage analysis with microsatellite markers spanning the Ulnar-Mammary locus at 12q24.1 did not confirm linkage. The patients may have a previously undescribed syndrome.

Small inherited terminal duplication of 7q with hydrocephalus, cleft palate, joint contractures, and severe hypotonia.

We report a 14-month-old girl with submucous cleft palate, resolving mild hydrocephalus, severe hypotonia and joint contractures. The finding of extreme hydrocephalus, cleft palate and club feet in a fetus of the mother's previous pregnancy suggested an inherited defect. Chromosome analysis and FISH studies in the proband revealed an abnormal homolog 13 resulting in a duplication of distal chromosome 7q, 7q35-qter, and a very small associated deletion of distal chromosome 13q, 13q34-qter. The mother showed the balanced translocation. Similar clinical signs have been described with larger distal 7q duplications. Our findings suggest that 7q35-qter, and possibly the gene for sonic hedgehog (SHH) on 7q36, is the critical region for the typical facial features and the profound hypotonia observed in the 'trisomy of distal 7q' syndrome.

Clinical and genetic heterogeneity in frontometaphyseal dysplasia: severe progressive scoliosis in two families.

Frontometaphyseal dysplasia is a rare genetic syndrome affecting the skeletal system and connective tissue. It is believed to be inherited as an X-linked trait. Features of frontometaphyseal dysplasia overlap with other skeletal dysplasias. Prominent supraorbital ridges, radiologic evidence of cranial hyperostosis, and flared metaphyses are characteristic. Scoliosis, a rare associated finding, is usually mild, and familial progressive scoliosis has not been reported so far. The skeletal dysplasia and the associated clinical findings show significant intra- and interfamilial variability. The syndrome has been suggested to be an allelic variant of the Melnick-Needles osteodysplasty, an X-linked (dominant) entity. We present two families with frontometaphyseal dysplasia, in which both males and females showed the facial and skeletal features of the syndrome in association with progressive scoliosis. Some of the affected members also had hearing loss and urogenital anomalies, supporting the existence of the recently suggested entity "fronto-otopalatodigital-osteodysplasty syndome".

Cleidocranial dysplasia with decreased bone density and biochemical findings of hypophosphatasia.

UNLABELLED: Cleidocranial dysplasia (CCD; MIM 119600) is an autosomal dominant skeletal dysplasia characterised by hypoplastic clavicles, patent fontanelles, short stature, tooth anomalies and other variable skeletal changes. Different mutations of the RUNX2/CBFA1 gene (MIM 600211) have been detected in patients with CCD. We investigated a mother and daughter with features of CCD presenting with reduced plasma alkaline phosphatase activity, increased urinary phosphoethanolamine excretion and decreased bone density. The latter findings were suggestive of hypophophatasia but mutation analysis showed no mutation in the tissue-nonspecific alkaline phosphatase gene (TNSALP; MIM 171760). However, a heterozygous mutation (Arg169Pro caused by nucleotide change 506G > C) was detected in the RUNX2 gene. Metabolic alterations gradually improved in both mother and daughter but bone-specific alkaline phosphatase remained low (less than 30% of normal) and mild phosphoethanolaminuria persisted. Recent studies in the Cbfa1 knock-out mouse showed decreased expression of alkaline phosphatase in differentiating bone. CONCLUSION: we suggest that the observed metabolic alterations are secondary to the RUNX2 gene mutation affecting early bone maturation and turnover. This is the first description of biochemical findings of hypophosphatasia in patients with cleidocranial dysplasia.