Variants in HCFC1 and MN1 genes causing intellectual disability in two Pakistani families.

BACKGROUND: Intellectual disability (ID) is a neurodevelopmental condition affecting around 2% of children and young adults worldwide, characterized by deficits in intellectual functioning and adaptive behavior. Genetic factors contribute to the development of ID phenotypes, including mutations and structural changes in chromosomes. Pathogenic variants in the HCFC1 gene cause X-linked mental retardation syndrome, also known as Siderius type X-linked mental retardation. The MN1 gene is necessary for palate development, and mutations in this gene result in a genetic condition called CEBALID syndrome. METHODS: Exome sequencing was used to identify the disease-causing variants in two affected families, A and B, from various regions of Pakistan. Affected individuals in these two families presented ID, developmental delay, and behavioral abnormalities. The validation and co-segregation analysis of the filtered variant was carried out using Sanger sequencing. RESULTS: In an X-linked family A, a novel hemizygous missense variant (c.5705G > A; p.Ser1902Asn) in the HCFC1 gene (NM_005334.3) was identified, while in family B exome sequencing revealed a heterozygous nonsense variant (c.3680 G > A; p. Trp1227Ter) in exon-1 of the MN1 gene (NM_032581.4). Sanger sequencing confirmed the segregation of these variants with ID in each family. CONCLUSIONS: The investigation of two Pakistani families revealed pathogenic genetic variants in the HCFC1 and MN1 genes, which cause ID and expand the mutational spectrum of these genes.

Brachyolmia, dental anomalies and short stature (DASS): Phenotype and genotype analyses of Egyptian and Pakistani patients.

Brachyolmia is a heterogeneous group of developmental disorders characterized by a short trunk, short stature, scoliosis, and generalized platyspondyly without significant deformities in the long bones. DASS (Dental Abnormalities and Short Stature), caused by alterations in the LTBP3 gene, was previously considered as a subtype of brachyolmia. The present study investigated three unrelated consanguineous families (A, B, C) with Brachyolmia and DASS from Egypt and Pakistan. In our Egyptian patients, we also observed hearing impairment. Exome sequencing was performed to determine the genetic causes of the diverse clinical conditions in the patients. Exome sequencing identified a novel homozygous splice acceptor site variant (LTBP3:c.3629-1G > T; p. ?) responsible for DASS phenotypes and a known homozygous missense variant (CABP2: c.590T > C; p.Ile197Thr) causing hearing impairment in the Egyptian patients. In addition, two previously reported homozygous frameshift variants (LTBP3:c.132delG; p.Pro45Argfs*25) and (LTBP3:c.2216delG; p.Gly739Alafs*7) were identified in Pakistani patients. This study emphasizes the vital role of LTBP3 in the axial skeleton and tooth morphogenesis and expands the mutational spectrum of LTBP3. We are reporting LTBP3 variants in seven patients of three families, majorly causing brachyolmia with dental and cardiac anomalies. Skeletal assessment documented short webbed neck, broad chest, evidences of mild long bones involvement, short distal phalanges, pes planus and osteopenic bone texture as additional associated findings expanding the clinical phenotype of DASS. The current study reveals that the hearing impairment phenotype in Egyptian patients of family A has a separate transmission mechanism independent of LTBP3.

Molecular insight into CREBBP and TANGO2 variants causing intellectual disability.

BACKGROUND: Intellectual disability (ID) can be associated with different syndromes such as Rubinstein-Taybi syndrome (RSTS) and can also be related to conditions such as metabolic encephalomyopathic crises, recurrent,with rhabdomyolysis, cardiac arrhythmias and neurodegeneration. Rare congenital RSTS1 (OMIM 180849) is characterized by mental and growth retardation, significant and duplicated distal phalanges of thumbs and halluces, facial dysmorphisms, and an elevated risk of malignancies. Microdeletions and point mutations in the CREB-binding protein (CREBBP) gene, located at 16p13.3, have been reported to cause RSTS. By contrast, TANGO2-related metabolic encephalopathy and arrhythmia (TRMEA) is a rare metabolic condition that causes repeated metabolic crises, hypoglycemia, lactic acidosis, rhabdomyolysis, arrhythmias and encephalopathy with cognitive decline. Clinicians need more clinical and genetic evidence to detect and comprehend the phenotypic spectrum of this disorder. METHODS: Exome sequencing was used to identify the disease-causing variants in two affected families A and B from District Kohat and District Karak, Khyber Pakhtunkhwa. Affected individuals from both families presented symptoms of ID, developmental delay and behavioral abnormalities. The validation and co-segregation analysis of the filtered variant was carried out using Sanger sequencing. RESULTS: In the present study, two families (A and B) exhibiting various forms of IDs were enrolled. In Family A, exome sequencing revealed a novel missense variant (NM 004380.3: c.4571A>G; NP_004371.2: p.Lys1524Arg) in the CREBBP gene, whereas, in Family B, a splice site variant (NM 152906.7: c.605 + 1G>A) in the TANGO2 gene was identified. Sanger sequencing of both variants confirmed their segregation with ID in both families. The in silico tools verified the aberrant changes in the CREBBP protein structure. Wild-type and mutant CREBBP protein structures were superimposed and conformational changes were observed likely altering the protein function. CONCLUSIONS: RSTS and TRMEA are exceedingly rare disorders for which specific clinical characteristics have been clearly established, but more investigations are underway and required. Multicenter studies are needed to increase our understanding of the clinical phenotypes, mainly showing the genotype-phenotype associations.

Structural and functional implications of SLC13A3 and SLC9A6 mutations: an in silico approach to understanding intellectual disability.

BACKGROUND: Intellectual disability (ID) is a condition that varies widely in both its clinical presentation and its genetic underpinnings. It significantly impacts patients' learning capacities and lowers their IQ below 70. The solute carrier (SLC) family is the most abundant class of transmembrane transporters and is responsible for the translocation of various substances across cell membranes, including nutrients, ions, metabolites, and medicines. The SLC13A3 gene encodes a plasma membrane-localized Na+/dicarboxylate cotransporter 3 (NaDC3) primarily expressed in the kidney, astrocytes, and the choroid plexus. In addition to three Na + ions, it brings four to six carbon dicarboxylates into the cytosol. Recently, it was discovered that patients with acute reversible leukoencephalopathy and a-ketoglutarate accumulation (ARLIAK) carry pathogenic mutations in the SLC13A3 gene, and the X-linked neurodevelopmental condition Christianson Syndrome is caused by mutations in the SLC9A6 gene, which encodes the recycling endosomal alkali cation/proton exchanger NHE6, also called sodium-hydrogen exchanger-6. As a result, there are severe impairments in the patient's mental capacity, physical skills, and adaptive behavior. METHODS AND RESULTS: Two Pakistani families (A and B) with autosomal recessive and X-linked intellectual disorders were clinically evaluated, and two novel disease-causing variants in the SLC13A3 gene (NM 022829.5) and the SLC9A6 gene (NM 001042537.2) were identified using whole exome sequencing. Family-A segregated a novel homozygous missense variant (c.1478 C > T; p. Pro493Leu) in the exon-11 of the SLC13A3 gene. At the same time, family-B segregated a novel missense variant (c.1342G > A; p.Gly448Arg) in the exon-10 of the SLC9A6 gene. By integrating computational approaches, our findings provided insights into the molecular mechanisms underlying the development of ID in individuals with SLC13A3 and SLC9A6 mutations. CONCLUSION: We have utilized in-silico tools in the current study to examine the deleterious effects of the identified variants, which carry the potential to understand the genotype-phenotype relationships in neurodevelopmental disorders.

Autosomal recessive variants c.953A>C and c.97-1G>C in NSUN2 causing intellectual disability: a molecular dynamics simulation study of loss-of-function mechanisms.

Introduction: Intellectual disability (ID) is a clinically and genetically heterogeneous disorder. It drastically affects the learning capabilities of patients and eventually reduces their IQ level below 70. Methods: The current genetic study ascertained two consanguineous Pakistani families suffering from autosomal recessive intellectual developmental disorder-5 (MRT5). We have used exome sequencing followed by Sanger sequencing to identify the disease-causing variants. Results and discussion: Genetic analysis using whole exome sequencing in these families identified two novel mutations in the NSUN2 (NM_017755.5). Family-A segregated a novel missense variant c.953A>C; p.Tyr318Ser in exon-9 of the NSUN2. The variant substituted an amino acid Tyr318, highly conserved among different animal species and located in the functional domain of NSUN2 known as "SAM-dependent methyltransferase RsmB/NOP2-type". Whereas in family B, we identified a novel splice site variant c.97-1G>C that affects the splice acceptor site of NSUN2. The identified splice variant (c.97-1G>C) was predicted to result in the skipping of exon-2, which would lead to a frameshift followed by a premature stop codon (p. His86Profs*16). Furthermore, it could result in the termination of translation and synthesis of dysfunctional protein, most likely leading to nonsense-mediated decay. The dynamic consequences of NSUN2 missense variant was further explored together with wildtype through molecular dynamic simulations, which uncovered the disruption of NSUN2 function due to a gain in structural flexibility. The present molecular genetic study further extends the mutational spectrum of NSUN2 to be involved in ID and its genetic heterogeneity in the Pakistani population.

Biallelic Variants in Seven Different Genes Associated with Clinically Suspected Bardet-Biedl Syndrome.

Bardet-Biedl syndrome (BBS) is a rare clinically and genetically heterogeneous autosomal recessive multi-systemic disorder with 22 known genes. The primary clinical and diagnostic features include six different hallmarks, such as rod-cone dystrophy, learning difficulties, renal abnormalities, male hypogonadism, post-axial polydactyly, and obesity. Here, we report nine consanguineous families and a non-consanguineous family with several affected individuals presenting typical clinical features of BBS. In the present study, 10 BBS Pakistani families were subjected to whole exome sequencing (WES), which revealed novel/recurrent gene variants, including a homozygous nonsense mutation (c.94C>T; p.Gln32Ter) in the IFT27 (NM_006860.5) gene in family A, a homozygous nonsense mutation (c.160A>T; p.Lys54Ter) in the BBIP1 (NM_001195306.1) gene in family B, a homozygous nonsense variant (c.720C>A; p.Cys240Ter) in the WDPCP (NM_015910.7) in family C, a homozygous nonsense variant (c.505A>T; p.Lys169Ter) in the LZTFL1 (NM_020347.4) in family D, pathogenic homozygous 1 bp deletion (c.775delA; p.Thr259Leufs*21) in the MKKS/BBS5 (NM_170784.3) gene in family E, a pathogenic homozygous missense variant (c.1339G>A; p.Ala447Thr) in BBS1 (NM_024649.4) in families F and G, a pathogenic homozygous donor splice site variant (c.951+1G>A; p?) in BBS1 (NM_024649.4) in family H, a pathogenic bi-allelic nonsense variant in MKKS (NM_170784.3) (c.119C>G; p.Ser40*) in family I, and homozygous pathogenic frameshift variants (c.196delA; p.Arg66Glufs*12) in BBS5 (NM_152384.3) in family J. Our findings extend the mutation and phenotypic spectrum of four different types of ciliopathies causing BBS and also support the importance of these genes in the development of multi-systemic human genetic disorders.

A novel frameshift variant in UBA2 causing split-hand/foot malformations in a Pakistani family.

Split-hand/foot malformation (SHFM) shows diverse heterogeneity and manifests with reduced penetrance and variable expressivity. This study investigated the underlying genetic cause of a family segregating SHFM. Exome sequencing followed by Sanger sequencing identified a novel single nucleotide heterozygous variant (NC_000019.9 (NM_005499.3):c.1118del) in UBA2 cosegregating in the family in an autosomal dominant manner. Our findings conclude that reduced penetrance and variable expressivity are the two remarkable and unusual features of SHFM.

The Expansion of the Spectrum in Stuttering Disorders to a Novel ARMC Gene Family (ARMC3).

Stuttering is a common neurodevelopment speech disorder that negatively affects the socio-psychological dimensions of people with disability. It displays many attributes of a complex genetic trait, and a few genetic loci have been identified through linkage studies. Stuttering is highly variable regarding its phenotypes and molecular etiology. However, all stutters have some common features, including blocks in speech, prolongation, and repetition of sounds, syllables, and words. The involuntary actions associated with stuttering often involve increased eye blinking, tremors of the lips or jaws, head jerks, clenched fists, perspiration, and cardiovascular changes. In the present study, we recruited a consanguineous Pakistani family showing an autosomal recessive mode of inheritance. The exome sequencing identified a homozygous splice site variant in ARMC3 (Armadillo Repeat Containing 3) in a consanguineous Pashtun family of Pakistani origin as the underlying genetic cause of non-syndromic stuttering. The homozygous splice site variant (NM_173081.5:c.916 + 1G > A) segregated with the stuttering phenotype in this family. The splice change leading to the skipping of exon-8 is a loss of function (LoF) variant, which is predicted to undergo NMD (Nonsense mediated decay). Here, we report ARMC3 as a novel candidate gene causing the stuttering phenotype. ARMC3 may lead to neurodevelopmental disorders, including stuttering in humans.

Chlorophyll fluorescence and grain filling characteristic of wheat (Triticum aestivum L.) in response to nitrogen application level.

BACKGROUND: This study aims to understand the influence of chlorophyll fluorescence parameters on yield of winter wheat in some areas of China. Nitrogen (N) application is believed to improve photosynthesis in flag leaf ultimately increase final yield. METHODS AND RESULTS: To understand the response of chlorophyll fluorescence parameters of wheat, flag leaf and the effect of N fertilization was carried out at booting stage under greenhouse during year 2018-2019 using winter wheat cultivar "Yunhan-20410' 'Yunhan-618". The results showed that the maximum chlorophyll content of flag leaves occurred at booting stage. Under, Yunhan-20410 condition, maximum photochemical quantum efficiency (FV/Fm), potential activity (ΦPSII), potential activity of PSII (FV/FO), and photochemical quenching coefficient (qp) showed "high-low" variation, and the maximum values were observed between May 4 and May 12. However, Yunhan-20410 showed FV/Fm, FV/FO, and qp showed "low-high-low" curve at booting stage. Compared to Yunhan-618, Yunhan-20410 at booting stage significantly decreased FV/Fm, FV/FO, qp, and ΦPSII (P<0.05), and non-photochemical quenching (NPQ) significantly increased (P<0.05). CONCLUSION: The outcome of present investigation suggest that chlorophyll fluorescence parameters could be valuable insight to understand yield stability under stress condition. Moreover, the investigated parameters could be useful criteria for selection of genotypes under varying nitrogen application levels.

Novel splicing-site mutation in DCAF17 gene causing Woodhouse-Sakati syndrome in a large consanguineous family.

BACKGROUND: Woodhouse-Sakati syndrome is a rare autosomal recessive disease with endocrine and neuroectodermal aberrations with heterogeneous phenotypes and disease course. The most common phenotypes of the disease are progressive sensorineural hearing loss and alopecia, mild-to-moderate mental retardation and hypogonadism. The disease results from mutations in the DCAF17 gene. METHOD: Here, we reported a large consanguineous pedigree with multiple affected individuals with Woodhouse-Sakati syndrome phenotypes. Laboratory tests confirmed the endocrine perturbance in affected individuals. To find out the underlying genetic change, whole-exome sequencing was carried out. RESULT: Analysis of the exome data identified a splicing-site deletion NM_025000.3:c.1423-1_1425delGACA in DCAF17 gene. Sanger sequencing confirmed the co-segregation of the variant with the disease phenotypes in the family. CONCLUSION: The variant is predicted to cause aberrant splicing, i.e., exon skipping, resulting in the translation of a truncated functionless protein which results in appearance of typical phenotypic features and clinical laboratory findings of Woodhouse-Sakati syndrome in affected members of the family.

The Growth, physiological and biochemical response of foxtail millet to atrazine herbicide.

Foxtail millet (Pennisetum glaucum L.) is a vital crop that is planted as food and fodder crop around the globe. There is only limited information is present for abiotic stresses on the physiological responses to atrazine. A field experiment was conducted to investigate the effects of different atrazine dosages on the growth, fluorescence and physiological parameters i.e., malonaldehyde (MDA) and reactive oxygen species (ROS) (H2O2 and O2) in the leaves to know the extent of atrazine on oxidative damage of foxtail millet. Our experiment consisted of 0, 2.5, 12.5, 22.5 and 32.5 (mg/kg) of labeled atrazine doses on 2 foxtaill millet varieties. High doses of atrazine significantly enhanced ROS and MDA synthesis in the plant leaves. Enzymes activities like ascorbate peroxidase (APX) and peroxidase (POD) activities enhanced, while catalase (CAD) and superoxide dismutase (SOD) activities reduced with increasing atrazine concentrations. Finally atrazine doses at 32.5 mg/kg reduced chlorophyll contents, while chlorophyll (a/b) ratio also enhanced. Biomass, plant height, chlorophyll fluorescence parameters, minimal and maximal fluorescence (Fo, Fm), maximum and actual quantum yield, photochemical quenching coefficient, and electron transport rate are decreased with increasing atrazine doses.

Whole Exome Sequencing Confirms Molecular Diagnostics of Three Pakhtun Families With Autosomal Recessive Epidermolysis Bullosa.

Epidermolysis bullosa (EB) is a genetic skin disorder that shows heterogeneous clinical fragility. The patients develop skin blisters congenitally or in the early years of life at the dermo-epithelial junctions, including erosions, hyperkeratosis over the palms and soles. The other associated features are hypotrichosis on the scalp, absent or dystrophic nails, and dental anomalies. Molecular diagnosis through whole-exome sequencing (WES) has become one of the successful tool in clinical setups. In this study, three Pakhtun families from the Khyber Pakhtunkhwa province of Pakistan were ascertained. WES analysis of a proband in each family revealed two novel variants (COL17A1: NM_000494.4: c.4041T>G: p.Y1347* and PLEC: NM_201380.3: c.1283_1285delGCT: p.L426del) and one previously known COL17A1: NM_000494.4:c.3067C>T: p.Q1023*) variant in homozygous forms. Sanger sequencing of the identified variants confirmed that the heterozygous genotypes of the obligate carriers. The identified variants have not only increased the mutation spectrum of the COL17A1 and PLEC but also confirms their vital role in the morphogenesis of skin and its associated appendages. WES can be used as a first-line diagnostic tool in genetic testing and counselling families from Khyber Pakhtunkhwa, Pakistan.

The First Report of a Missense Variant in RFX2 Causing Non-Syndromic Tooth Agenesis in a Consanguineous Pakistani Family.

Background: The syndromic and non-syndromic congenital missing teeth phenotype is termed tooth agenesis. Since tooth agenesis is a heterogeneous disorder hence, the patients show diverse absent teeth phenotypes. Thus identifying novel genes involved in the morphogenesis of ectodermal appendages, including teeth, paves the way for establishing signaling pathways. Methods and Results: We have recruited an autosomal recessive non-syndromic tooth agenesis family with two affected members. The exome sequencing technology identified a novel missense sequence variant c.1421T > C; p.(Ile474Thr) in a regulatory factor X (RFX) family member (RFX2, OMIM: 142,765). During the data analysis eight rare variants on various chromosomal locations were identified, but the co-segregation analysis using Sanger sequencing confirmed the segregation of only two variants RFX2: c.1421T > C; p.(Ile474Thr), DOHH: c.109C > G; p.(Pro37Ala) lying in a common 7.1 MB region of homozygosity on chromosome 19p13.3. Furthermore, the online protein prediction algorithms and protein modeling analysis verified the RFX2 variant as a damaging genetic alteration and ACMG pathogenicity criteria classified it as likely pathogenic. On the other hand, the DOHH variant showed benign outcomes. Conclusion: RFX2 regulates the Hedgehog and fibroblast growth factor signaling pathways, which are involved in the epithelial and mesenchymal interactions during tooth development. Prior animal model studies have confirmed the expression of rfx2 at a developmental stage governing mouth formation. Moreover, its regulatory role and close association with ciliary and non-ciliary genes causing various dental malformations makes it a potential candidate gene for tooth agenesis phenotype. Further studies will contribute to exploring the direct role of RFX2 in human tooth development.

Homozygous variants of EDAR underlying hypohidrotic ectodermal dysplasia in three consanguineous families.

BACKGROUND: Hypohidrotic ectodermal dysplasia (HED) is a congenital anomaly characterized by hypohydrosis, hypotrichosis and hypodontia. Mutations in at least four genes (EDAR, EDARADD, WNT10A, TRAF6) have been reported to cause both autosomal recessive and autosomal dominant forms of HED. Mutations in two other genes (EDA and IKBKG) have been reported to cause X-linked HED. OBJECTIVES: To clinically characterize three consanguineous families (A-C) segregating with autosomal recessive HED and identify possible disease-causing variants of EDAR and EDARADD genes. MATERIALS AND METHODS: The genes, EDAR and EDARADD, were sequenced in Family A and C, and exome sequencing was performed in Family B. Additionally, in Family A and C, the effect of the identified variants was examined by analysis of EDAR mRNA, extracted from hair follicles from both affected and unaffected members. RESULTS: Sequence analysis revealed three possible disease-causing EDAR variants including a novel splice acceptor site variant (IVS3-1G > A) in Family A and two previously reported mutations (p.[Ala26Val], p.[Arg25*]) in the two other families. Previously, the nonsense variant p.(Arg25*) was reported only in the heterozygous state. Analysis of the RNA, extracted from hair follicles, revealed skipping of a downstream exon in EDAR and complete degradation of EDAR mRNA in affected members in family A and C, respectively. Computational modelling validated the pathogenic effect of the two variants identified in Family B and C. CONCLUSION: The three variants reported here expand the spectrum of EDAR mutations associated with HED which may further facilitate genetic counselling of families segregating with similar disorders in the Pakistani population.

[Allelopathic effects of water extracts from different parts of foxtail millet straw on three kinds of weeds]. / 谷子秸秆不同部位水浸液对3种杂草的化感作用.

We examined the allelopathic effect of extracts from different parts of foxtail millet straw with different concentrations (undiluted water extracts, 10-fold, 50-fold, and 100-fold dilution) on three different kinds of malignant weeds (Amaranthus retroflexus, Chenopodium album, and Setaria viridis) by water extract. In this experiment, we measured biological indicators for seed germination period and potted seedling physiological parameters. The results showed that water extract of foxtail millet leaves and stems had significant allelopathic effects on the three species of weeds, with the effects of different concentrations being different. Undiluted water extract inhibited the growth, while dilution (10-fold, 50-fold, 100-fold dilution) promoted the growth. Under the treatment of undiluted water extract of leaf and stem, the germination rate of three weeds decreased 63.9%, 37.3% and 41.7%, respectively, while root length was only 27.8%, 37.8% and 18.4% of the control. The bud length was only 34.5%, 27.7% and 17.6% of the control. The net photosynthetic rate accounted for 66.6%, 89.9% and 88.2% of the control. The transpiration rate accounted for 69.0%, 87.5% and 56.1% of the control, while the synthesis allelopathic index of the three weeds were -0.699, -0.716 and -0.795 by undiluted water extract, respectively. Results implied strong allelopathic inhibition. The allelopathy promoting effect of dilution increased first and then decreased with the increases of dilution folds. Among which, 50-fold dilution had the strongest promoting effect with the germination rate, root length and bud length of the three weeds being significantly different from those of the control, with the synthesis allelopathic index being 0.261, 0.217, and 0.165, respectively. A large number of associated weeds grow in foxtail millet field which is related to the leaching of allelopathic substances in straw.

A novel nonsense variant in SLC24A4 causing a rare form of amelogenesis imperfecta in a Pakistani family.

BACKGROUND: Amelogenesis imperfecta (AI) is a highly heterogeneous group of hereditary developmental abnormalities which mainly affects the dental enamel during tooth development in terms of its thickness, structure, and composition. It appears both in syndromic as well as non-syndromic forms. In the affected individuals, the enamel is usually thin, soft, rough, brittle, pitted, chipped, and abraded, having reduced functional ability and aesthetics. It leads to severe complications in the patient, like early tooth loss, severe discomfort, pain, dental caries, chewing difficulties, and discoloration of teeth from yellow to yellowish-brown or creamy type. The study aimed to identify the disease-causing variant in a consanguineous family. METHODS: We recruited a consanguineous Pashtun family of Pakistani origin. Exome sequencing analysis was followed by Sanger sequencing to identify the pathogenic variant in this family. RESULTS: Clinical analysis revealed hypomaturation AI having generalized yellow-brown or creamy type of discoloration in affected members. We identified a novel nonsense sequence variant c.1192C > T (p.Gln398*) in exon-12 of SLC24A4 by using exome sequencing. Later, its co-segregation within the family was confirmed by Sanger sequencing. The human gene mutation database (HGMD, 2019) has a record of five pathogenic variants in SLC24A4, causing AI phenotype. CONCLUSION: This nonsense sequence variant c.1192C > T (p.Gln398*) is the sixth disease-causing variant in SLC24A4, which extends its mutation spectrum and confirms the role of this gene in the morphogenesis of human tooth enamel. The identified variant highlights the critical role of SLC24A4 in causing a rare AI type in humans.

Adsorption of Cd and Pb in contaminated gleysol by composite treatment of sepiolite, organic manure and lime in field and batch experiments.

Contamination of arable land with trace metals is a global environmental issue which has serious consequences on human health and food security. Present study evaluates the adsorption of cadmium (Cd) and lead (Pb) by using different quantities of composite of sepiolite, organic manure and lime (SOL) at field and laboratory scale (batch experiments). Characterization of SOL by SEM, EDS and FTIR spectroscopy revealed the presence of elemental and functional groups (hydroxyl, C⋯H and -COOH groups) on its surface. The field experiment was performed in a paddy field of gleysol having moderate contamination of Cd and Pb (0.64 mg kg-1 and 53.44 mg kg-1). Here, different rates of SOL (0.25, 0.5, 1, 1.5 and 2% w/w) were applied by growing low and high Cd accumulator rice cultivars. Application of SOL at 2% w/w showed considerable efficiency to increase soil pH (up to 19%) and to reduce available Cd (42-66%) and Pb (22-55%) as compared to the control. Moreover, its application reduced metal contents in roots, shoots and grains of rice by 31%, 36% and 72% (for Cd) and 41%, 81% and 84% (for Pb), respectively in low accumulator cultivar. Further, the batch sorption experiment was performed to evaluate the adsorption capacity of SOL in a wide range of contamination. Obtained sorption data was better fitted to the Langmuir equation. Our results highlight the strong efficiency of composite treatment for an enhanced in-situ metal immobilization under field and lab conditions. Further, applied treatments greatly reduced the metal contents in rice grains. In a nut shell, application of SOL in a contaminated gleysol should be considered for soil remediation and safe food production.

Association of sequence variants in frizzled-6 with autosomal recessive nail dysplasia (NDNC-10) in Pashtun families.

Primitive epidermis develops the nail apparatus. Nails have a strong and inflexible nail plate at the end of each digit. Very few genes responsible for causing nonsyndromic form of nail dysplasia have been reported. In the current study, peripheral blood samples were collectedfrom three unaffected individuals and four affectedindividuals of Family A, while blood from two affected and three unaffected individuals were taken of Family B. Genotyping in both the families was performed using highly polymorphic short tandem repeat microsatellite markers. Sanger sequence of the FZD6 gene was performed and analysed for segregation analysis. A comparative modelling approach was used to predict the three-dimensional structures of FZD-6 protein using Modeller 4. Linkage analysis mapped a disease locus on chromosome 8q22.3, harbouring FZD6. Targeted Sanger sequencing of all the coding exons of FZD6 revealed a nonsense sequence variant in pedigree A, whereas a missense sequence variant in pedigree B. Finding and literature indicates the disease spectrum of Pakistani population with claw-shaped nail dysplasia, particularly in families of Pashtun origin.

Deleterious Variants in WNT10A, EDAR, and EDA Causing Isolated and Syndromic Tooth Agenesis: A Structural Perspective from Molecular Dynamics Simulations.

The dental abnormalities are the typical features of many ectodermal dysplasias along with congenital malformations of nails, skin, hair, and sweat glands. However, several reports of non-syndromic/isolated tooth agenesis have also been found in the literature. The characteristic features of hypohidrotic ectodermal dysplasia (HED) comprise of hypodontia/oligodontia, along with hypohidrosis/anhidrosis, and hypotrichosis. Pathogenic variants in EDA, EDAR, EDARADD, and TRAF6, cause the phenotypic expression of HED. Genetic alterations in EDA and WNT10A cause particularly non-syndromic/isolated oligodontia. In the current project, we recruited 57 patients of 17 genetic pedigrees (A-Q) from different geographic regions of the world, including Pakistan, Egypt, Saudi Arabia, and Syria. The molecular investigation of different syndromic and non-syndromic dental conditions, including hypodontia, oligodontia, generalized odontodysplasia, and dental crowding was carried out by using exome and Sanger sequencing. We have identified a novel missense variant (c.311G>A; p.Arg104His) in WNT10A in three oligodontia patients of family A, two novel sequence variants (c.207delinsTT, p.Gly70Trpfs*25 and c.1300T>G; p.Try434Gly) in EDAR in three patients of family B and four patients of family C, respectively. To better understand the structural and functional consequences of missense variants in WNT10A and EDAR on the stability of the proteins, we have performed extensive molecular dynamic (MD) simulations. We have also identified three previously reported pathogenic variants (c.1076T>C; p.Met359Thr), (c.1133C>T; p.Thr378Met) and (c.594_595insC; Gly201Argfs*39) in EDA in family D (four patients), E (two patients) and F (one patient), correspondingly. Presently, our data explain the genetic cause of 18 syndromic and non-syndromic tooth agenesis patients in six autosomal recessive and X-linked pedigrees (A-F), which expand the mutational spectrum of these unique clinical manifestations.

Research Progress and Perspective on Drought Stress in Legumes: A Review.

Climate change, food shortage, water scarcity, and population growth are some of the threatening challenges being faced in today's world. Drought stress (DS) poses a constant challenge for agricultural crops and has been considered a severe constraint for global agricultural productivity; its intensity and severity are predicted to increase in the near future. Legumes demonstrate high sensitivity to DS, especially at vegetative and reproductive stages. They are mostly grown in the dry areas and are moderately drought tolerant, but severe DS leads to remarkable production losses. The most prominent effects of DS are reduced germination, stunted growth, serious damage to the photosynthetic apparatus, decrease in net photosynthesis, and a reduction in nutrient uptake. To curb the catastrophic effect of DS in legumes, it is imperative to understand its effects, mechanisms, and the agronomic and genetic basis of drought for sustainable management. This review highlights the impact of DS on legumes, mechanisms, and proposes appropriate management approaches to alleviate the severity of water stress. In our discussion, we outline the influence of water stress on physiological aspects (such as germination, photosynthesis, water and nutrient uptake), growth parameters and yield. Additionally, mechanisms, various management strategies, for instance, agronomic practices (planting time and geometry, nutrient management), plant growth-promoting Rhizobacteria and arbuscular mycorrhizal fungal inoculation, quantitative trait loci (QTLs), functional genomics and advanced strategies (CRISPR-Cas9) are also critically discussed. We propose that the integration of several approaches such as agronomic and biotechnological strategies as well as advanced genome editing tools is needed to develop drought-tolerant legume cultivars.