Significance of Maternal Serum Folate and Vitamin B12 levels with Factor V leiden, Factor II g.20210G>A, MTHFR C667T and MTHFR A1298C variations in Anencephaly

AimExact etiology of multifactorial anencephaly is still unclear. For a better understanding of the etiology, we sought to determine serum levels of folate and vitamin B12 as well as genetic variations including Factor V Leiden, Factor II g.20210G>A, MTHFR c.667C>T and MTHFR c.1298A>C in pregnant Turkish women with fetal anencephaly, and healthy pregnant women to point out significant differences.Material-MethodsWe compared the concentration of serum folate, vitamin B12 and genotype related with Factor V Leiden (FVL), Factor II (FII) G20210A, MTHFR C667T and MTHFR A1298C variations in 10 pregnant mothers with fetal anencephaly, and 32 mothers with healthy pregnancies. Gene polymorphisms were genotyped using Real-Time PCR.ResultsWe found a significant difference in serum folate concentrations and MTHFR A1298C genotypes between groups. However, serum B12 vitamin concentrations and Factor V Leiden, Factor II G20210A, and MTHFR C667T genotypes were not significantly different in mothers with fetal anencephaly, compared to controls.ConclusionLow maternal folate level is a known factor in the development of anencephaly and neural tube defects. Studies indicating an association with MTHFR gene polymorphisms are also present. We have determined that the lack of folic acid plays an important role in the etiology of anencephaly, however other factors are not significant. We believe that more research is needed as the etiology of anencephaly is still not fully understood

Evaluation of <i>Factor V Leiden, Prothrombin G20210A, MTHFR C677T</i> and <i>MTHFR A1298C</i> gene polymorphisms in retinopathy of prematurity in a Turkish cohort

<p><i>Background</i>: To assess <i>Factor V Leiden (FVL)</i> (rs6025), <i>Prothrombin G20210A</i> (rs1799963), <i>MTHFR C677T</i> (rs1801133), and <i>MTHFR A1298C</i> (rs1801131) gene mutations as risk factors in the development of retinopathy of prematurity (ROP).</p> <p><i>Materials and methods</i>: A total of 105 children were included in this cross-sectional study. Patients were divided into two groups. The study group consisted of 55 infants with a history of ROP and the control group comprised 50 healthy infants with term birth. All subjects were screened for the presence of certain mutations (<i>FVL, Prothrombin G20210A, MTHFR C677T</i> and <i>MTHFR A1298C</i>) by Real-Time PCR at 1 year of age.</p> <p><i>Results</i>: The mean gestational age (GA) and birth weight (BW) of the study group were, 28.65 ± 2.85 weeks and 1171 ± 385.74 g, respectively. There were no significant differences of genotype and allele frequency of <i>Prothrombin G20210A, MTHFR A1298C</i> and <i>MTHFR C677T</i> between the study and control groups (<i>p</i> > 0.05). Eight children (14.5 %) had heterozygous and one child (1.8%) had homozygous <i>FVL</i> mutation in the study group. One child (2%) in the control group had heterozygous <i>FVL</i> mutation. There was statistically significant differences of <i>FVL</i> allele and genotype frequencies between the groups (<i>p</i> < 0.05).</p> <p><i>Conclusions</i>: The prevalence of <i>FVL</i> polymorphism (16.3 %) was higher in ROP patients than control subjects in this Turkish cohort. We suggest a possible association of <i>FVL</i> mutation with ROP at the end of the study.</p

Prenatal diagnosis and outcome of lymphangiomas and its relationship with fetal chromosomal abnormalities

Objectives: Our aim was to evaluate ultrasound findings and perinatal outcome after prenatal diagnosis of lymphangioma.Methods: This was a retrospective case series study. We searched the archives of our ultrasound database at our center for cases with the prenatal diagnosis of the lymphangioma in the period between January 2008 and November 2014. We described maternal, fetal and perinatal variables for all cases.Results: Nine fetuses with lymphangioma were identified. All cases were diagnosed during the second and third trimesters with the average gestational age of 22.63.9 weeks. The average diameter of lymphangioma was 55.4 +/- 20.1mm at the time of diagnosis. Five fetuses (55.6%) had lymphangioma on the neck, and four fetuses (44.4%) had lymphangioma on other localizations. Normal fetal karyotype was detected in all cases. There were a total of six live births, one intrauterine death and two medical terminations of pregnancy following the diagnosis of lymphangioma. No abnormal Doppler finding or hydrops were detected in the antenatal follow-up of remaining six cases.Conclusion: The risk of chromosomal abnormalities is very low in pregnancies with isolated lymphangioma. The outcome of pregnancies with lymphangioma is generally favorable and prognosis depends on their locations and size

A novel frameshift mutation and infrequent clinical findings in two cases with Dyggve-Melchior-Clausen syndrome

Dyggve-Melchior-Clausen syndrome (DMC) (MIM #223800) is a rare autosomal-recessive type of skeletal dysplasia accompanied by variable degrees of intellectual disability (ID). It is characterized by progressive spondyloepimetaphyseal dysplasia leading to disproportionate short stature, microcephaly, and coarse facies. The radiographic appearance of generalized platyspondyly with double-humped end plates and the lace-like appearance of iliac crests are pathognomonic in this syndrome. The disorder results from mutations in the dymeclin (DYM) mapped to the 18q12-12.1 chromosomal region. Here, we report two cases with DMC: one with disproportionate short stature, developmental delay, and severe ID with a novel frameshift mutation (c.1028_1056del29) leading to a premature stop codon, and the second patient with classical clinical and radiological features of DMC with mild ID and rectal prolapse, which is very rare. The clinical diagnosis was confirmed with molecular analysis of DYM with a known mutation at c.580C>T (p.R194X). The parents and sibling of the second patient were heterozygous carriers with mild skeletal changes and short stature

Prenatal diagnosis and outcome of lymphangiomas and its relationship with fetal chromosomal abnormalities

Objectives: Our aim was to evaluate ultrasound findings and perinatal outcome after prenatal diagnosis of lymphangioma.Methods: This was a retrospective case series study. We searched the archives of our ultrasound database at our center for cases with the prenatal diagnosis of the lymphangioma in the period between January 2008 and November 2014. We described maternal, fetal and perinatal variables for all cases.Results: Nine fetuses with lymphangioma were identified. All cases were diagnosed during the second and third trimesters with the average gestational age of 22.63.9 weeks. The average diameter of lymphangioma was 55.4 +/- 20.1mm at the time of diagnosis. Five fetuses (55.6%) had lymphangioma on the neck, and four fetuses (44.4%) had lymphangioma on other localizations. Normal fetal karyotype was detected in all cases. There were a total of six live births, one intrauterine death and two medical terminations of pregnancy following the diagnosis of lymphangioma. No abnormal Doppler finding or hydrops were detected in the antenatal follow-up of remaining six cases.Conclusion: The risk of chromosomal abnormalities is very low in pregnancies with isolated lymphangioma. The outcome of pregnancies with lymphangioma is generally favorable and prognosis depends on their locations and size

Molecular etiology of arthrogryposis in multiple families of mostly Turkish origin

BACKGROUND. Arthrogryposis, defined as congenital, joint contractures in 2 or more body areas, is a clinical sign rather than a specific disease diagnosis. To date, more than 400 different disorders have been described that present with arthrogryposis, and variants of more than 220 genes have been associated with these disorders; however, the underlying molecular etiology remains unknown in the considerable majority of these cases

Loss of non-motor kinesin KIF26A causes congenital brain malformations via dysregulated neuronal migration and axonal growth as well as apoptosis.

Kinesins are canonical molecular motors but can also function as modulators of intracellular signaling. KIF26A, an unconventional kinesin that lacks motor activity, inhibits growth-factor-receptor-bound protein 2 (GRB2)- and focal adhesion kinase (FAK)-dependent signal transduction, but its functions in the brain have not been characterized. We report a patient cohort with biallelic loss-of-function variants in KIF26A, exhibiting a spectrum of congenital brain malformations. In the developing brain, KIF26A is preferentially expressed during early- and mid-gestation in excitatory neurons. Combining mice and human iPSC-derived organoid models, we discovered that loss of KIF26A causes excitatory neuron-specific defects in radial migration, localization, dendritic and axonal growth, and apoptosis, offering a convincing explanation of the disease etiology in patients. Single-cell RNA sequencing in KIF26A knockout organoids revealed transcriptional changes in MAPK, MYC, and E2F pathways. Our findings illustrate the pathogenesis of KIF26A loss-of-function variants and identify the surprising versatility of this non-motor kinesin

Molecular etiology of arthrogryposis in multiple families of mostly Turkish origin

BACKGROUND. Arthrogryposis, defined as congenital joint contractures in 2 or more body areas, is a clinical sign rather than a specific disease diagnosis. To date, more than 400 different disorders have been described that present with arthrogryposis, and variants of more than 220 genes have been associated with these disorders; however, the underlying molecular etiology remains unknown in the considerable majority of these cases. METHODS. We performed whole exome sequencing (WES) of 52 patients with clinical presentation of arthrogryposis from 48 different families. RESULTS. Affected individuals from 17 families (35.4%) had variants in known arthrogryposis-associated genes, including homozygous variants of cholinergic γ nicotinic receptor (CHRNG, 6 subjects) and endothelin converting enzyme–like 1 (ECEL1, 4 subjects). Deleterious variants in candidate arthrogryposis-causing genes (fibrillin 3 [FBN3], myosin IXA [MYO9A], and pleckstrin and Sec7 domain containing 3 [PSD3]) were identified in 3 families (6.2%). Moreover, in 8 families with a homozygous mutation in an arthrogryposis-associated gene, we identified a second locus with either a homozygous or compound heterozygous variant in a candidate gene (myosin binding protein C, fast type [MYBPC2] and vacuolar protein sorting 8 [VPS8], 2 families, 4.2%) or in another disease-associated genes (6 families, 12.5%), indicating a potential mutational burden contributing to disease expression. CONCLUSION. In 58.3% of families, the arthrogryposis manifestation could be explained by a molecular diagnosis; however, the molecular etiology in subjects from 20 families remained unsolved by WES. Only 5 of these 20 unrelated subjects had a clinical presentation consistent with amyoplasia; a phenotype not thought to be of genetic origin. Our results indicate that increased use of genome-wide technologies will provide opportunities to better understand genetic models for diseases and molecular mechanisms of genetically heterogeneous disorders, such as arthrogryposis. FUNDING. This work was supported in part by US National Human Genome Research Institute (NHGRI)/National Heart, Lung, and Blood Institute (NHLBI) grant U54HG006542 to the Baylor-Hopkins Center for Mendelian Genomics, and US National Institute of Neurological Disorders and Stroke (NINDS) grant R01NS058529 to J.R. Lupski

Global transcriptional disturbances underlie Cornelia de Lange syndrome and related phenotypes

Cornelia de Lange syndrome (CdLS) is a genetically heterogeneous disorder that presents with extensive phenotypic variability, including facial dysmorphism, developmental delay/intellectual disability (DD/ID), abnormal extremities, and hirsutism. About 65% of patients harbor mutations in genes that encode subunits or regulators of the cohesin complex, including NIPBL, SMC1A, SMC3, RAD21, and HDAC8. Wiedemann-Steiner syndrome (WDSTS), which shares CdLS phenotypic features, is caused by mutations in lysine-specific methyltransferase 2A (KMT2A). Here, we performed whole-exome sequencing (WES) of 2 male siblings clinically diagnosed with WDSTS; this revealed a hemizygous, missense mutation in SMC1A that was predicted to be deleterious. Extensive clinical evaluation and WES of 32 Turkish patients clinically diagnosed with CdLS revealed the presence of a de novo heterozygous nonsense KMT2A mutation in 1 patient without characteristic WDSTS features. We also identified de nova heterozygous mutations in SMC3 or SMC1A that affected RNA splicing in 2 independent patients with combined CdLS and WDSTS features. Furthermore, in families from 2 separate world populations segregating an autosomal-recessive disorder with CdLS-like features, we identified homozygous mutations in TAF6, which encodes a core transcriptional regulatory pathway component. Together, our data, along with recent transcriptome studies, suggest that CdLS and related phenotypes may be "transcriptomopathies" rather than cohesinopathies