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Background Wolfram syndrome (WFS) is characterized by deafness, diabetes mellitus, and diabetes insipidus along with optic atrophy. WFS has an autosomal recessive mode of inheritance and is due to variants in WFS1 and CISD2. Methods We evaluated the underlying molecular etiology of three affected members of a consanguineous family with hearing impairment, bicuspid aortic valve, diabetes mellitus and insipidus, clinodactyly, and gastrointestinal tract abnormalities via exome sequencing approach. We correlated clinical and imaging data with the genetic findings and their associated phenotypes. Results We identified a homozygous missense variant p.(Asn1097Lys) in CDK13, a gene previously associated with autosomal dominant congenital heart defects, dysmorphic facial features, clinodactyly, gastrointestinal tract abnormalities, intellectual developmental disorder, and seizures with variable phenotypic features. Conclusion We report a homozygous variant in CDK13 and suggest that this gene causes an autosomal recessive disorder with hearing impairment, bicuspid aortic valve, diabetes mellitus and insipidus, clinodactyly, and gastrointestinal tract abnormalities.

Summary Background Hereditary hypertrichosis (HH) is characterized by excessive hair growth on various body areas, which is independent of the individual's age. This rare hair disorder has been classified by its origin (genetic or acquired), age of onset, breadth of hair distribution (universal or localized) and the affected body areas. HH is often linked to several additional congenital abnormalities involving teeth, heart and bones. Human HH is associated with heterozygous genomic duplications and deletions in the chromosomal region 17q24.2–q24.3, containing genes such as ABCA5, ABCA6, ABCA10 and MAP2K6. Recently, a homozygous splice-site variant in ABCA5 has been reported to cause autosomal recessive congenital generalized hypertrichosis terminalis (CGHT; OMIM 135400). Aim To investigate the clinical and genetic basis of autosomal recessive hypertrichosis in a large consanguineous Pakistani family. Methods In the present study, we characterized a family of Pakistani origin segregating CGHT in an autosomal recessive pattern, using whole exome sequencing followed by Sanger sequencing Results We identified a novel 2-bp intragenic deletion [NM_172232.4(ABCA5);c.977_978delAT] causing a frameshift variant (p.His326ArgfsTer5) in ABCA5. Conclusions To our knowledge, this is the first intragenic deletion in ABCA5 underlying CGHT. The findings further validate the involvement of ABCA5 in hair development. The study will facilitate genetic counselling of families carrying CGHT-related features in Pakistani and other populations.

Aim: To analyze clinical, biochemical & treatment profile of patients suffering from CLD secondary to viral hepatitis in our region. Duration & place of study: Descriptive study, January 2021 to July 2021 at Frontier Medical & Dental College, Abbottabad Methods: All patients having chronic liver disease secondary to viral hepatitis with or without complications were enrolled in this study. A diagnosis was made based on clinical findings, biochemical tests, ultrasonography of abdomen and upper GI endoscopy findings. Inclusion criteria further included presence of stigmata suggestive of chronic liver disease and clinical and laboratory parameters which were indicative of portal hypertension. Patients who refused to give consent, pregnant female patients and patients suffering from CLD caused by etiological factors other than hepatitis viruses and who were terminally ill were excluded. Results: Mean age of these patients was 41.25±12.59 years. There were 138 males and only 16 female patients. Majority of the patients, 79.22%, developed anorexia. A large number of patients, 82.47%, had hepatomegaly while 58.44% had firmness in their liver. About 79.87% had splenomegaly, 66.23% had spider naevi, 86.36% had ascites and 87.67% had esophageal varices. Almost half of our patients, 50.65%, used steroid therapy while a large majority of them, 85.06%, were taking antiviral treatment. Mean values of bilirubin, alkaline phosphatase, alanine aminotransferase (ALT), albumin and prothrombin time (PT) were 1.43±1.21 mg/dL, 105.33±51.51 U/L, 85.89±89.65 U/L, 3.82±0.65 g/dL, 62.57±22 seconds respectively. Conclusion: Chronic liver disease secondary to viral hepatitis especially hepatitis B and C virus is quite common in our country. It presents with typical stigmata both clinically and pathologically. There is a need to identify these stigmata and diagnose this condition early to avoid complications in these patients. Keywords: Hepatitis, antiviral, hepatomegaly, liver, bilirubin

The underlying work includes the time-dependent flow and improved thermal transport for tangent hyperbolic nanofluids across an extending wedge. Self-motile microorganisms are suspended in the fluid to avoid agglomeration of tiny particles. Moreover, magnetic field, heat source, convectively heated boundary, and activation energy are considered. Mathematical formulation based on usual laws of conservation is non dimensionalized with emerging parameters through implementation of similarity transform to yield a corresponding set of ordinary partial differential equations. In the face of convective non linearity, a finite element discretization is harnessed to be coded and run on Matlab platform. The parametric calculation are carried out for faster and slower wedge. The rising strength of wedge angle, unsteadiness, and material law index recede the velocity distribution. The distribution of temperature upgrades directly against growing of Hartman number, thermophoresis, Biot number, material law index, and Brownian motion parameters. The concentration profile of nanoparticles decrease against Lewis number and activation energy, but it rises directly with higher input of activation energy. The computational results obtained through Matlab code blocks are corroborated with the existing literature and found to be a tolerable correlation.

Leukocyte adhesion deficiency I (LADI) is an autosomal recessive type of primary immunodeficiency characterized by occurrence of repeated bacterial infections, impaired pus formation and wound healing. Genetic variations in the β-2 integrin subunit encoding gene ITGB2 have been implicated in causing the disorder. In the present study, we have investigated twelve patients presenting LAD1 features. After collecting clinical and family history, flow cytometry was used to determine levels of CD18 in the patients. Clinical history revealed that umbilical cord separation occurred mostly after 19 days in the patients. Recurrent skin infections were found in seven patients. Eight patients had at least one elder sibling who died due to repeated infections. All patients had marked neutrophilia with only 0.77% of neutrophils expressing CD18. Total 12 patients suffering from LAD1 were Sanger sequenced for ITGB2 gene. Five variants, including a novel p.(Cys286Phe) and four previously reported [p.(Gly273Arg), p.(Asp128Tyr), p.(Cys62*), IVS7 + 1G > A] were identified in 8 cases, while no pathogenic variant was observed in remaining four cases. This study represents the first comprehensive clinical and genetic characterization of LAD1 in Pakistani population. This will facilitate diagnosis and genetic counselling of patients with immunodeficiency disorders in Pakistani population.

Sinoatrial node dysfunction and deafness (SANDD) syndrome is rare and characterized by a low heart beat and severe-to-profound deafness. Additional features include fatigue, dizziness, and episodic syncope. The sinoatrial node (SAN) drives heart automaticity and continuously regulates heart rate. The CACNA1D gene encoding the Ca(v)1.3 protein expressed in inner hair cells, atria and SAN, induces loss-of-function in channel activity and underlies SANDD. To date, only one variant c.1208_1209insGGG:p.(G403_V404insG) has been reported for SANDD syndrome. We studied five Pakistani families with SANDD and characterized a new missense variant p.(A376V) in CACNA1D in one family, and further characterized the founder variant p.(G403_V404insG) in four additional pedigrees. We show that affected individuals in the four families which segregate p.(G403_V404insG) share a 1.03 MB haplotype on 3p21.1 suggesting they share a common distant ancestor. In conclusion, we identified new and known variants in CACNA1D in five Pakistani families with SANDD. This study is of clinical importance as the CACNA1D founder variant is only observed in families from the Khyber Pakhtunkhwa (KPK) province, in Pakistan. Therefore, screening patients with congenital deafness for SAN dysfunction in this province could ensure adequate follow-up and prevent cardiac failure associated with SAN.

R-Spondins regulate the WNT/β-catenin signaling pathway by interacting with leucine rich-repeat containing G-protein coupled receptors (LGR4–6). These receptors share unique sequence and structural similarities with each other. Here, we report comparative binding analysis of R-Spondin-4 (RSPO4) with LGRs through structural characterization of a missense variant (GLY67ARG) identified in two consanguineous families of Pakistani origin. The modeled structure of RSPO4 comprises two contiguous Furin-like cysteine-rich domains that are involved in binding with LGRs. We observed an overall conservation of overlapping interacting residues among LGRs which recognized RSPO4 at two specific parallel positions (sites ‘a’ and ‘b’). The residual contributions of RSPO4 reconciled previously defined interactions of RSPO1 with LGRs. To check the comparative expression pattern of β-catenin, we quantified β-catenin levels in normal and anonychia patients. β-catenin level was significantly reduced in the patients exhibiting mutated RSPO4 as compared to control individuals. These findings confirm that RSPO4 modulates the LGR-dependent WNT/β-catenin signaling pathway and may have therapeutic potential in anonychia patients.

Genetic deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS) due to mutations in the GALNS gene results in the pathogenesis of Morquio A syndrome. To date, more than 200 mutations have been reported in GALNS, resulting in variable clinical features. For this reason, bioinformatics analysis of these mutations is important to determine their effect on the structure and functions of the protein and to establish a correlation between genotype and phenotype. In the present study, eight Pakistani consanguineous families with Morquio A syndrome were clinically and genetically evaluated. Linkage analysis followed by sequence analysis of the gene detected four novel (p.Phe216Ser, p.Met38Arg, p.Ala291Ser, p.Glu121Argfs*37) and two reported (p.Pro420Arg, p.Arg386Cys) mutations in the eight families. In silico structural and functional analysis predicted that these mutations disrupt the function of GALNS protein through fluctuating its three-dimensional structure, stability, and binding affinity and produce severe phenotypes. This is the first comprehensive study on molecular analysis of patients with Morquio A syndrome from Pakistan that reports four novel mutations with their structural and functional consequences.

Spencer et al. report the first description of human IL-6R deficiency in two patients presenting with recurrent infections, atopy, elevated IgE, and abnormal acute-phase responses., IL-6 excess is central to the pathogenesis of multiple inflammatory conditions and is targeted in clinical practice by immunotherapy that blocks the IL-6 receptor encoded by IL6R. We describe two patients with homozygous mutations in IL6R who presented with recurrent infections, abnormal acute-phase responses, elevated IgE, eczema, and eosinophilia. This study identifies a novel primary immunodeficiency, clarifying the contribution of IL-6 to the phenotype of patients with mutations in IL6ST, STAT3, and ZNF341, genes encoding different components of the IL-6 signaling pathway, and alerts us to the potential toxicity of drugs targeting the IL-6R.

The sphingosine-1-phosphate receptors (S1PRs) are a well-studied class of transmembrane G protein-coupled sphingolipid receptors that mediate multiple cellular processes. However, S1PRs have not been previously reported to be involved in the genetic etiology of human traits. S1PR2 lies within the autosomal-recessive nonsyndromic hearing impairment (ARNSHI) locus DFNB68 on 19p13.2. From exome sequence data we identified two pathogenic S1PR2 variants, c.323GC (p.Arg108Pro) and c.419AG (p.Tyr140Cys). Each of these variants co-segregates with congenital profound hearing impairment in consanguineous Pakistani families with maximum LOD scores of 6.4 for family DEM4154 and 3.3 for family PKDF1400. Neither S1PR2 missense variant was reported among ∼120,000 chromosomes in the Exome Aggregation Consortium database, in 76 unrelated Pakistani exomes, or in 720 Pakistani control chromosomes. Both DNA variants affect highly conserved residues of S1PR2 and are predicted to be damaging by multiple bioinformatics tools. Molecular modeling predicts that these variants affect binding of sphingosine-1-phosphate (p.Arg108Pro) and G protein docking (p.Tyr140Cys). In the previously reported S1pr2(-/-) mice, stria vascularis abnormalities, organ of Corti degeneration, and profound hearing loss were observed. Additionally, hair cell defects were seen in both knockout mice and morphant zebrafish. Family PKDF1400 presents with ARNSHI, which is consistent with the lack of gross malformations in S1pr2(-/-) mice, whereas family DEM4154 has lower limb malformations in addition to hearing loss. Our findings suggest the possibility of developing therapies against hair cell damage (e.g., from ototoxic drugs) through targeted stimulation of S1PR2.

Homozygous and/or heterozygous loss of function mutations in the natriuretic peptide receptor B (NPR2) have been reported in causing acromesomelic dysplasia, type Maroteaux with variable clinical features and idiopathic short stature with nonspecific skeletal deformities. On the other hand, gain of function mutations in the same gene result in overgrowth disorder suggesting that NPR2 and its ligand, natriuretic peptide precursor C (CNP), are the key players of endochondral bone growth. However, the precise mechanism behind phenotypic variability of the NPR2 mutations is not fully understood so far. In the present study, three consanguineous families of Pakistani origin (A, B, C) with variable phenotypes of acromesomelic dysplasia, type Maroteaux were evaluated at clinical and molecular levels. Linkage analysis followed by Sanger sequencing of the NPR2 gene revealed three homozygous mutations including p.(Leu314 Arg), p.(Arg371*), and p.(Arg1032*) in family A, B and C, respectively. In silico structural and functional analyses substantiated that a novel missense mutation [p.(Leu314 Arg)] in family A allosterically affects binding of NPR2 homodimer to its ligand (CNP) which ultimately results in defective guanylate cyclase activity. A nonsense mutation [p.(Arg371*)] in family B entirely removed the transmembrane domain, protein kinase domain and guanylate cyclase domains of the NPR2 resulting in abolishing its guanylate cyclase activity. Another novel mutation [p.(Arg1032*)], found in family C, deteriorated the guanylate cyclase domain of the protein and probably plundered its guanylate cyclase activity. These results suggest that guanylate cyclase activity is the most critical function of the NPR2 and phenotypic severity of the NPR2 mutations is proportional to the reduction in its guanylate cyclase activity.

Background Woolly hair (WH) is a hair abnormality that is primarily characterised by tightly curled hair with abnormal growth. Methods In two unrelated consanguineous Pakistani families with non-syndromic autosomal recessive (AR) WH, homozygosity mapping and linkage analysis identified a locus within 17q21.1–q22, which contains the type I keratin gene cluster. A DNA sample from an affected individual from each family underwent exome sequencing. Results A homozygous missense variant c.950T>C (p.(Leu317Pro)) within KRT25 segregated with ARWH in both families, and has a combined maximum two-point LOD score of 7.9 at ϴ=0. The KRT25 variant is predicted to result in disruption of the second α-helical rod domain and the entire protein structure, thus possibly interfering with heterodimerisation of K25 with type II keratins within the inner root sheath (IRS) of the hair follicle and the medulla of the hair shaft. Conclusions Our findings implicate a novel gene involved in human hair abnormality, and are consistent with the curled, fragile hair found in mice with Krt25 mutations, and further support the role of IRS-specific type I keratins in hair follicle development and maintenance of hair texture.

Applications well-defined with high Fault Tolerance index are considered reliable and trustworthy to drive quality. Fault Tolerance metrics for web mobile applications are neither defined formally nor are they organized at a single place for measurement to researchers and quality engineers. Fault Tolerance metrics determines the quality of web mobile applications provided they are measured accurately. There is a phenomenal gap between Fault Tolerance (FT) metrics development and measurement for web based mobile applications. Unfortunately, existing research has failed in providing a precise and well-organized definition for Fault Tolerance metrics in the domain of web mobile applications. This has led to inadequate Fault Tolerance metrics to perfectly measure and benchmark modern day web mobile applications. This research work has developed a comprehensive Fault Tolerance Metrics Framework, targeting Web and Mobile Applications to measure associated quality attributes by applying GQM technique. Dispersed FT attributes are identified and organized from existing Quality Models and standards. Sub factors have been well defined using standard units in line with web architectures. Particularly, this research applies Systematic Mathematical formulation to quantify Fault Tolerance to target web mobile applications. Further Fault Tolerance is measured and evaluated through an experimental study designed on target web mobile applications.

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Summary Background Autosomal recessive hypotrichosis is a rare human hereditary disorder presenting as sparse scalp hair or as woolly hair occurring on various parts of the body. Various forms of isolated hypotrichosis have been reported to date. Mutations in at least 11 genes have been reported to cause hypotrichosis. Aims To investigate the clinical and genetic basis of autosomal recessive hypotrichosis in two unrelated consanguineous families. Methods Genotyping by highly polymorphic microsatellite markers established linkage in both families to the DSG4 gene on chromosome 18q21. PCR amplification of exons and intron–exon borders of the DSG4 gene was performed, and the products sequenced to search for disease-causing sequence variants. Results Clinical investigation revealed typical hypotrichosis in the affected members of one family, while other affected members showed presence of monilethrix-like scalp hair. Sequence analysis of DSG4 revealed a novel deletion mutation (c.85-1_191del) in the affected subjects of both families. Conclusions This study further extends the body of evidence that mutations in the DSG4 gene result in both hypotrichosis and monilethrix-like scalp hair.

Summary Background Inherited isolated nail anomaly manifesting with onychauxis and onycholysis is a rare condition, caused by mutations in the gene FZD6, encoding membrane-bound Wnt receptor protein. Objectives To search for sequence variants in the gene FZD6 in three individuals of a consanguineous family exhibiting features of nail dysplasia. Methods Linkage in the family was searched by genotyping microsatellite markers linked to the gene FZD6, mapped at chromosome 8q22.3. Exons and splice junction sites of the gene FZD6 were polymerase chain reaction amplified and sequenced in an automated DNA sequencer. Results DNA sequence analysis revealed a novel homozygous missense mutation (c.1266G>A; p.Gly422Asp) located in the transmembrane domain of the protein FZD6. Conclusions The missense mutation (p.Gly422Asp), identified here, is only the third mutation detected in the gene FZD6.

Hereditary hypotrichosis is a rare autosomal recessive disorder characterized by sparse hair on scalp and rest of the body of affected individuals. Two forms of such hypotrichosis LAH and AH have been mapped on chromosome 18q12.1 and 3q27, respectively. Mutations in desmogelin 4 (DSG4) gene have been reported to underlie LAH. Recently, a deletion mutation in Lipase H (LIPH) gene, located at AH locus, has been identified in two ethnic groups of Russian population. In the present study, a four generation Pakistani family with AH phenotype has been mapped to chromosome 3q27. Sequence analysis of candidate gene LIPH revealed a novel five base pair deletion mutation (c.346-350delATATA) in exon 2 of the gene leading to frameshift and downstream premature termination codon. The mutation reported in the family, presented here, is the second mutation identified in LIPH gene. The identification of a genetic defect in LIPH suggests that this enzyme regulates hair growth.

Ellis-van Creveld syndrome (EVC) is a rare developmental disorder characterized by short limbs, short ribs, postaxial polydactyly, dysplastic nails, teeth, oral and cardiac abnormalities. It is caused by biallelic mutations in the EVC or EVC2 gene, separated by 2.6 kb of genomic sequence on chromosome 4p16. In the present study, we have investigated two consanguineous families of Pakistani origin, segregating EVC in autosomal recessive manner. Linkage in the families was established to chromosome 4p16. Subsequently, sequence analysis identified a novel nonsense mutation (p.Trp234*) in exon 8 of the EVC2 gene and 15 bp duplication in exon 14 of the EVC gene in the two families. This further expands the mutations in the EVC or EVC2 genes resulting in the EVC syndrome.

• We presented the first report of Xp22.3 micro-deletions underlying isolated XLI in seventeen familial cases representing major ethnic groups living in Pakistan.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder affecting upper motor neurons in the brain and lower motor neurons in the brain stem and spinal cord, resulting in fatal paralysis. It has been found to be associated with frontotemporal lobar degeneration (FTLD). In the present study, we have described homozygosity mapping and gene sequencing in a consanguineous autosomal recessive Pakistani family showing non-juvenile ALS without signs of FTLD. Gene mapping was carried out in all recruited family members using microsatellite markers, and linkage was established with sigma non-opioid intracellular receptor 1 (SIGMAR1) gene at chromosome 9p13.2. Gene sequencing of SIGMAR1 revealed a novel 3'-UTR nucleotide variation c.672*31A>G (rs4879809) segregating with disease in this family. The C9ORF72 repeat region in intron 1, previously implicated in a related phenotype, was excluded through linkage, and further confirmation of exclusion was obtained by amplifying intron 1 of C9ORF72 with multiple primers in affected individuals and controls. In silico analysis was carried out to explore the possible role of 3'-UTR variant of SIGMAR1 in ALS. The Regulatory RNA motif and Element Finder program revealed disturbance in miRNA (hsa-miR-1205) binding site due to this variation. ESEFinder analysis showed new SRSF1 and SRSF1-IgM-BRCA1 binding sites with significant scores due to this variation. Our results indicate that the 3'-UTR SIGMAR1 variant c.672*31A>G may have a role in the pathogenesis of ALS in this family.

Background Atrichia with papular lesions (APL) is a rare irreversible form of complete hair loss inherited in autosomal recessive manner. Hair loss is often followed by the appearance of multiple keratin-filled cysts or papules on exterior parts of the body. This phenotype results due to mutations in the human hairless gene (HR) mapped on chromosome 8p21.3. The present study was aimed to search for disease-causing sequence variants in the HR gene in five consanguineous families exhibiting features of APL. Methods Linkage in five Pakistani lineal consanguineous families, displaying features of APL, was tested using microsatellite markers flanking the HR gene on chromosome 8p21.3. After constructing the haplotypes, variants in the gene HR were searched by dideoxy-chain termination sequencing. Results Haplotype analysis established linkage in all five families to the HR gene located on chromosome 8p.21.3. Subsequently, sequencing HR identified a novel homozygous nonsense variant (c.2541G>A, p.Trp847*) in one and previously reported two pathogenic variants (p.Cys690*, p.Pro1157Arg) in the other four families. Conclusion Mutations identified extend the spectrum of mutations in the HR gene resulting in APL. Characterizing the clinical spectrum resulting from the disease-causing homozygous variants in the HR gene will direct clinical care of the family members.

Ectodermal dysplasias (EDs) belong to a group of genetic diseases which result from alterations in ectoderm-derived appendages including hair, nail, teeth and sweat glands. Ectodermal dysplasia syndactyly syndrome (EDSS1) is one of the rare forms of ED caused by mutations in nectin-4, encoded by the PVRL4 gene. The present study described clinical investigation of the EDSS1 identified in a large consanguineous family. Furthermore, DNA sequence analysis revealed a novel homozygous nonsense mutation (181CT, p.Asp61*) in the PVRL4 gene.

To determine the cut-off values of anthropometric indices to indicate insulin resistance and correlation of these indices with insulin resistance in Pakistani adults.The cross-sectional study was conducted at the Military Hospital and Army Medical College, Rawalpindi, Pakistan, from June 2010 to November 2011. The study measured 209 adults for body mass index, waist circumference, waist-to-hip ratio, waist-to-height ratio and conicity index. Receiver operating characteristics curve analyses were done to determine the predictive values of these anthropometric measures and their cut-off values for insulin resistance by triglyceride/high density lipoprotein ratio.Overall mean age was 51.5 +/- 1.16 years (range: 28-73) and there were 136 (65%) males and 73 (35%) females. Body mass index had the maximum predictive value for insulin resistance followed by waist circumference and waist-to-height ratio in males (p0.0001), sensitivity and specificity being 68% and 62% respectively with cut-off value of 25.04 kg/m2. ROC curve analyses showed the maximum predictive value of conicity index for insulin resistance followed by waist circumference and waist-to-height ratio in females (p0.08), sensitivity and specificity being 65% and 50% respectively with cut-off value of 1.39.In Pakistani male adults, BMI is the best indicator of insulin resistance, while in female adults, conicity index is the best indicator.This is the first study in Pakistan reporting predictive values of anthropometric indices as a non-invasive method in determining insulin resistance.

Autosomal recessive hypotrichosis is a rare genetic irreversible hair loss disorder characterized by sparse scalp hair, sparse to absent eyebrows and eyelashes, and sparse axillary and body hair. The study, presented here, established genetic linkage in four families showing similar phenotypes to lysophosphatidic acid receptor 6 (LPAR6) gene on chromosome 13q14.11-q21.32. Subsequently, sequence analysis of the gene revealed two previously reported missense mutations including p.D63V in affected members of one and p.I188F in three other families. Molecular modeling and docking analysis was performed to investigate binding of a ligand oleoyl-L-alpha-lysophosphatidic acid (LPA) to modeled protein structures of normal and mutated (D63V, G146R, I188F, N248Y, S3T, L277P) LPAR6 receptors. The mutant receptors showed a complete shift in orientation of LPA at the binding site. In addition, hydropathy analysis revealed a significant change in the membrane spanning topology of LPAR6 helical segments. The present study further substantiated involvement of LPAR6-LPA signaling in the pathogenesis of hypotrichosis/woolly hair and provided additional insight into the molecular mechanism of hair development.

Inherited deafness is clinically and genetically heterogeneous. We recently mapped DFNB86, a locus associated with nonsyndromic deafness, to chromosome 16p. In this study, whole-exome sequencing was performed with genomic DNA from affected individuals from three large consanguineous families in which markers linked to DFNB86 segregate with profound deafness. Analyses of these data revealed homozygous mutation c.208G>T (p.Asp70Tyr) or c.878G>C (p.Arg293Pro) in TBC1D24 as the underlying cause of deafness in the three families. Sanger sequence analysis of TBC1D24 in an additional large family in which deafness segregates with DFNB86 identified the c.208G>T (p.Asp70Tyr) substitution. These mutations affect TBC1D24 amino acid residues that are conserved in orthologs ranging from fruit fly to human. Neither variant was observed in databases of single-nucleotide variants or in 634 chromosomes from ethnically matched control subjects. TBC1D24 in the mouse inner ear was immunolocalized predominantly to spiral ganglion neurons, indicating that DFNB86 deafness might be an auditory neuropathy spectrum disorder. Previously, six recessive mutations in TBC1D24 were reported to cause seizures (hearing loss was not reported) ranging in severity from epilepsy with otherwise normal development to epileptic encephalopathy resulting in childhood death. Two of our four families in which deafness segregates with mutant alleles of TBC1D24 were available for neurological examination. Cosegregation of epilepsy and deafness was not observed in these two families. Although the causal relationship between genotype and phenotype is not presently understood, our findings, combined with published data, indicate that recessive alleles of TBC1D24 can cause either epilepsy or nonsyndromic deafness.

Autosomal recessive primary microcephaly (MCPH) is a heterogeneous disorder which mainly affects neurodevelopment. Generally, MCPH patients exhibit mild brain structural anomalies and simplified cerebral cortex, but few recently identified genes are associated with severe brain malformations. Here, we report a five generation Pakistani family with three affected individuals presenting primary microcephaly, intellectual disability, schizencephaly and hypoplasia of corpus callosum. The comparison of available clinical information led to candidate gene mapping and sequencing of WD repeat domain 62 (WDR62) gene which is mostly associated with severe brain malformations. A homozygous deletion mutation c.1143delA was detected in exon 9 of WDR62 gene, in all affected individuals, which resulted in frameshift and protein truncation (p.H381PfsX48). This study supports the frequent involvement of WDR62 in patients with gross brain malformations.

Autosomal recessive primary microcephaly (MCPH) is a rare human genetic disorder in which the head circumference is reduced because of abnormality in fetal brain growth. To date, six loci and four genes have been identified for this condition. Our study of primary MCPH led to the identification of 33 Pakistani families with different ethnic backgrounds. Most of these families showed linkage to MCPH5 locus on chromosome 1q31. Only one family with Pashtoon origin from a remote region in Pakistan linked to MCPH6 locus on chromosome 13q12.12–q12.13. Sequence analysis of exon 11 of CENPJ gene, located at MCPH6 locus, revealed a novel four base pair deletion mutation, which is predicted to be protein truncating.

Objectives Localized autosomal recessive hypotrichosis is a non-syndromic human hair loss disorder, affecting scalp, eyebrows and eyelashes, and other parts of the body. Six consanguineous families with this form of hair loss disorder were investigated at both the clinical and molecular levels. Methods Linkage in six families with twenty-one affected members was tested by genotyping microsatellite markers linked to autosomal recessive hypotrichosis loci including localized autosomal recessive hypotrichosis (LAH) 1, 2 and 3. Sequence analysis of the entire coding and splice sites of the gene DSG4 was performed to search for the disease-causing mutation. Results Genotyping established linkage in families to the DSG4 gene at LAH1 locus on chromosome 18q21.1. Sequence analysis detected an intragenic deletion mutation (Ex5_8 del) in affected members of all six families. Conclusion Identification of recurrent mutation in six additional Pakistani families strengthens the body of evidence that this is an ancestral mutation that is widespread among different Pakistani ethnic groups.

IL-6 excess is central to the pathogenesis of multiple inflammatory conditions and this is targeted in clinical practice by immunotherapy that blocks the IL-6 receptor encoded by IL6R. We describe two patients with homozygous mutations in IL6R who presented with recurrent infections, abnormal acute phase responses, elevated IgE, eczema, and eosinophilia. This study identifies a novel primary immunodeficiency, clarifying the contribution of IL-6 to the phenotype of patients with mutations in IL6ST, STAT3 and ZNF341, genes encoding different components of the IL-6 signalling pathway, and alerts us to the potential toxicity of drugs targeting the IL-6R., J.E.D.T. is supported by the MRC (RG95376 and MR/L006197/1). KB is supported by the European Research Council (ERC StG 310857) and the Austrian Science Fund (P29951-B30). This work is supported, in part, by the intramural research program of the NIAID, NIH. A.J.T. is supported by the Wellcome Trust (104807/Z/14/Z) and the NIHR Biomedical Research Centre at Great Ormond Street Hospital for Children NHS Foundation Trust and University College London. KGCS is supported by the Medical Research Council (program grant MR/L019027) and is a Wellcome Investigator. M.G. and S.T. are supported in part by Cancer Research UK. RCA and MT are supported by a DOC fellowship of the Austrian Academy of Sciences. This research was made possible through access to the data and findings generated by two pilot studies for the 100,000 Genomes Project. The enrolment for one pilot study was coordinated by the NIHR BioResource (preprint from doi: https://doi.org/10.1101/507244) and the other by Genomics England Limited (GEL), a wholly owned company of the Department of Health in the UK. Over 90% of participants in the pilot studies have been enrolled in the NIHR BioResource. These pilot studies were mainly funded by grants from the National Institute for Health Research (NIHR) in England to the University of Cambridge and GEL, respectively. Additional funding was provided by the BHF, MRC, NHS England, the Wellcome Trust, amongst many other funders. The pilot studies use data provided by patients and their close relatives and collected by the NHS and other healthcare providers as part of their care and support. We thank all volunteers for their participation, and also gratefully acknowledge NIHR Biomedical Research Centres, NIHR BioResource Centres, NHS Trust Hospitals, NHS Blood and Transplant and staff for their contribution. ST is on the scientific advisory board for Ipsen, and is a consultant for Kallyope Inc. The authors declare no competing financial interests.

Background A rare neuro-ichthyotic disorder characterized by ichthyosis, spastic quadriplegia and intellectual disability and caused by recessive mutations in ELOVL4, encoding elongase-4 protein has recently been described. The objective of the study was to search for sequence variants in the gene ELOVL4 in three affected individuals of a consanguineous Pakistani family exhibiting features of neuro-ichthyotic disorder. Methods Linkage in the family was searched by genotyping microsatellite markers linked to the gene ELOVL4, mapped at chromosome 6p14.1. Exons and splice junction sites of the gene ELOVL4 were polymerase chain reaction amplified and sequenced in an automated DNA sequencer. Results DNA sequence analysis revealed a novel homozygous nonsense mutation (c.78C > G; p.Tyr26*). Conclusions Our report further confirms the recently described ELOVL4-related neuro-ichthyosis and shows that the neurological phenotype can be absent in some individuals.