We identified the PACS2 gene responsible for the multifunctional sorting protein that play a role in nuclear gene expression as well as pathway traffic regulation. Diseases associated with PACS2 include early infantile epileptic encephalopathy (EIEE66), alacrima, achalasia, and mental retardation syndrome. Whole exome sequencing (WES) technique was used for the identification of variants that may lead to the disease. We identified a consanguineous Saudi family segregating developmental delay, mental retardation and epilepsy. Our results showed a heterozygous missense variant PACS2 gene leading to intellectual disability, epilepsy and cause epileptic encephalopathies (EIEE66) disorder. WES data was analyzed and identified variants were further confirmed by Sanger sequencing validation technique. We identified a heterozygous missense c.625G>A p.Glu209Lys in exon-6 of PACS2. The detected heterozygous mutation in the exon-6 region of PACS2 gene change the protein features and may cause disease. Further, explain the possibility that PACS2 gene play important role to cause intellectual disability, epilepsy and epileptic encephalopathies in this Saudi family.

Leukodystrophies are a diverse group of genetically established disorders categorized by unusual white matter changes on brain imaging. Hypomyelinating leukodystrophies (HLDs) are a group of neurodevelopmental disorders that affect myelin sheath development in the brain. These disorders are categorized as developmental delay, spasticity, hypotonia, and intellectual disabilities. We describe a patient with developmental delay, cerebellar ataxia, spasticity, hypotonia, and intellectual disability from a healthy family member. Whole exome sequencing (WES) was performed to identify causative variants, which were further analyzed by bioinformatic analysis. WES was performed, and Sanger sequencing-based segregation analysis confirmed the presence of the homozygous missense variants of NM_203290.3 c.934T > C p.Ser312Pro of RNA polymerase I and III subunit C (POLR1C) gene in this patient and heterozygous variant in the unaffected carrier father and mother, supporting the pathogenicity and inheritance pattern of this variant. Furthermore, the variant identified by WES was validated in healthy controls (n = 100) using Sanger sequencing analysis. Finally, our study explained the important use of WES in disease diagnosis and provided further evidence that the variant in the POLR1C gene may play an important role in the development of hypomyelinating leukodystrophy in Saudi families.

Ehlers-Danlos syndrome (EDS) is a group of clinically and genetically heterogeneous disorder of soft connective tissues. The hallmark clinical features of the EDS are hyperextensible skin, hypermobile joints, and fragile vessels. It exhibits associated symptoms including contractures of muscles, kyphoscoliosis, spondylodysplasia, dermatosparaxis, periodontitis, and arthrochalasia. The aim of this study is to determine the exact subtype of EDS by molecular genetic testing in a family segregating EDS in an autosomal recessive manner. Herein, we describe a family with two individuals afflicted with EDS. Whole exome sequencing identified a homozygous missense mutation (c.2050G > A; p.Glu684Lys) in the COL1A1 gene in both affected individuals, although heterozygous variants in the COL1A1 are known to cause EDS. Recently, only one report showed homozygous variant as an underlying cause of the EDS in two Saudi families. This is the second report of a homozygous variant in the COL1A1 gene in a family of Saudi origin. Heterozygous carriers of COL1A1 variant are asymptomatic. Interestingly, the homozygous variant identified previously and the one identified in this study are same (c.2050G > A). The identification of a unique homozygous mutation (c.2050G > A) in three Saudi families argues in favor of a founder effect.

Intellectual developmental disorder with abnormal behavior, microcephaly and short stature (IDDABS), (OMIM# 618342) is an autosomal recessive condition described as developmental delay, poor or absent speech, intellectual disability, short stature, mild to progressive microcephaly, delayed psychomotor development, hyperactivity, seizure, along with mild to swear aggressive behavior. Homozygous frameshift mutation in Pseudouridine Synthase 7, Putative; (PUS7) OMIM# 616,261 NM_019042.3 and splice acceptor variants in Alpha-Aminoadipic Semialdehyde Synthase; (AASS) OMIM# 605,113 NM_005763.3 was funded. Whole exome sequencing (WES) technique was used as tool to identify the molecular diagnostic test. Different bioinformatics analysis done for WES data and we identified two novel mutations one as frameshift mutation c.606_607delGA, p.Ser282CysfsTer9 in the PUS7 gene and splice acceptor variants c.1767-1 G > A in the AASS gene has been reported. The pattern of family segregation maintained the pathogenicity of this variation associated with abnormal behavior, intellectual developmental disorder, microcephaly along with short stature IDDABS. Further, the WES data was validated in the family having other affected individuals and healthy controls (n = 100) was done using Sanger sequencing. Finally, our results further explained the role of WES in the disease diagnosis and elucidated that the mutation in PUS7 and AASS genes may lead an important role for the development of IDDABS in Saudi family.

UNASSIGNED: To study the causative variants in affected member of a Saudi family with Tay-Sachs disorder. This disorder includes paralysis, decreasing in attentiveness, seizures, blindness, motor deterioration progresses rapidly leading to a completely unresponsive state and a cherry-red spot visible on the eye.
UNASSIGNED: Whole exome sequencing (WES) and Sanger sequencing was performed to study the variant leading to the disease.
UNASSIGNED: WES data analysis and Sanger sequencing validation, identifies a homozygous nonsense mutation c.1177C>T, p.Arg393Ter as a result in protein change. This mutation was also studied in 100 unrelated healthy controls.
UNASSIGNED: We detected homozygous mutation in HEXA gene that may lead to cause Tay-Sachs disorder. Moreover, explain the possibility that HEXA gene may play important role for multiple aspects of normal human neurodevelopment.

Intellectual developmental disorder with dysmorphic facies and ptosis is an autosomal dominant condition characterized by delayed psychomotor development, intellectual disability, delayed speech, and dysmorphic facial features, mostly ptosis. Heterozygous mutations in bromodomain and plant homeodomain (PHD) finger containing one (BRPF1) gene have been reported. In this study, whole exome sequencing (WES) was performed as a molecular diagnostic test. Bioinformatics of WES data and candidate gene prioritization identified a novel variant in heterozygous state in the exon 3 of BRPF1 gene (ENST383829: c.1054G > C and p.Val352Leu). Autosomal dominant inheritance in the family affected individuals and exclusion of non-pathogenicity in the ethnically matched healthy controls (n = 100) were performed by Sanger sequencing. To the best of our knowledge, this is the first evidence of BRPF1 variant in a Saudi family. Whole exome sequencing analysis has been proven as a valuable tool in the molecular diagnostics. Our findings further expand the role of WES in efficient disease diagnosis in Arab families and explained that the mutation in BRPF1 gene plays an important role for the development of IDDFP syndrome.

UNASSIGNED: Primary microcephaly (MCPH) is a rare autosomal recessive disorder characterized by impaired congenital reduction of brain size along with head circumference and intellectual disability. MCPH is a heterogeneous disorder and more than twenty four genes associated with this disease have been identified so far. The objective of this study was to find out the novel genes or mutations leading to the genetic defect in a Saudi family with primary microcephaly.
UNASSIGNED: Whole exome sequencing was carried out to find the novel mutation and the results was further validated using Sanger sequencing analysis. This study was done in the Center of excellence in Genomic Medicine and Research, King Abdulaziz University under KACST project during 2017 and 2018.
UNASSIGNED: We report a novel compound heterozygous mutations c.797C>T in exon 7 and c.1102G>A in exon 9 of the WD repeat domain 62 (WDR62) (OMIM 604317) gene in two affected siblings in Saudi family with intellectual disability, speech impediments walking difficulty along with primary microcephaly. Two rare, missense variants were detected in heterozygous state in the WDR62 gene in these two affected individuals from the heterozygous parents.
UNASSIGNED: A compound heterozygous mutations c.797C>T in exon 7 and c.1102G> A in exon 9 of the WDR62 gene was identified. WDR62 gene is very important gene and mutation can lead to neuro developmental defects, brain malformations, reduced brain and head size. These results should be taken into consideration during prognostic discussions and mutation spectrum with affected patients and their families in the Saudi population.

Background A do-not-resuscitate (DNR) order is a medical decision that instructs healthcare providers to withhold cardiopulmonary resuscitations (CPR) to patients in case of cardiopulmonary arrest in respect to their wishes. In Saudi Arabia, the decision is usually made by physicians based on the Fatwa number 12086 regardless of the patients\' or their families\' desires. Assessing the knowledge, perception, and attitude of Saudi family members towards this medical decision may help guide medical practitioners to make decisions that are legally and ethically acceptable for the patients and their family. Therefore, this study aimed to assess their knowledge, perception, and attitude about DNR decisions and to determine demographic variables that affect their attitude towards DNR decisions. Method This cross-sectional study was conducted from December 2017 to January 2018 utilizing survey distribution through emails and different social media outlets including Facebook, Twitter, Pinterest, and LinkedIn. A self-administered questionnaire was employed to elicit responses regarding knowledge, perception, and attitude towards DNR decisions. Statistical Package for the Social Sciences Windows version 17 (SPSS v.17) (IBM Corporation, USA) was used for data management and analysis. Result Of the 1882 participants who filled the questionnaire, only 1693 participants were eligible as the study sample population and were included in the final data analysis. Most of the participants were from the Makkah region (72.2%) and were mainly from the general population (61.66%). Participants were mainly females (66%) and within the median age of 30 years (IQR: 21). As expected, participants who had heard about the DNR practice were from the medical field (58.6%) and they were mainly distant relatives. Almost 76% of the participants had two to four incorrect answers about the DNR practice, and it indicated that participants have inadequate knowledge about a DNR order. Most of the participants (43.2%) refused to be on a DNR order if they were diagnosed with a terminal illness. However, most participants (69.9%) wanted to have an involvement in the decision-making of being on a DNR order. In terms of willingness to understand and learn about the DNR decision, 1475 (87.1%) of the participants wanted to learn more about the DNR practice. Being a relative of a terminally ill cancer patient did not have a significant effect on the knowledge and perceptions of participants about being on a DNR order. However, having a background in medicine was found to be significantly associated with their acceptance to be on a DNR order. The knowledge score regarding DNR was found to be significantly associated with higher acceptance towards DNR orders. Conclusion The majority of participants had a lack of knowledge about the DNR practice. Their religion\'s concept of hope and virtue is considered as the major reason for their DNR order refusal. However, proper education about the DNR practice and involvement in the DNR order decision-making will increase the participants\' knowledge and will improve their acceptance of the DNR practice.

Progressive encephalopathy, edema, hypsarrhythmia, and optic atrophy (PEHO) syndrome is an unusual Mendelian phenotype of unidentified origin that causes profound intellectual disability, optic nerve/cerebellar atrophy, epileptic seizures, developmental progress, pedal edema, and early death. Uncharacteristic affected individuals are often classified as having PEHO-like syndrome, although they may be misdiagnosed as having epileptic encephalopathy, a potential result of early birth. In this study, we report a consanguineous Saudi family with a novel homozygous nonsense mutation of the CCDC88A gene causing PEHO-like syndrome. The children were suffering from developmental delay, epilepsy, mental disability, optic nerve/cerebellar atrophy, and pedal edema. Whole exome sequencing was conducted for the members of the family who have the disorder to study the novel mutation. Whole exome sequencing data analysis, confirmed by subsequent Sanger sequencing validation, identified a novel homozygous nonsense mutation c. 1292G > A, which was caused by p.Trp431* stop gain. This mutation was ruled out in 100 unrelated healthy controls. The nonsense homozygous mutation detected in this study has not yet been reported as pathogenic in the literature or various databases. In conclusion, a complete loss of protein function due to premature stop gain was caused by a mutation in exon 12 of CCDC88A. This loss may lead to PEHO phenotype. CCDC88A gene may therefore play an important and critical role for multiple aspects of normal human neurodevelopment.

Epileptic encephalopathies are genetically heterogeneous disorders which leads to epilepsy and cause neurological disorders. Seizure threshold 2 (SZT2) gene located on chromosome 1p34.2 encodes protein mainly expressed predominantly in the parietal and frontal cortex and dorsal root ganglia in the brain. Previous studies in mice showed that mutation in this gene can confers low seizure threshold, enhance epileptogenesis and in human may leads to facial dysmorphism, intellectual disability, seizure and macrocephaly. Objective of this study was to find out novel gene or novel mutation related to the gene phenotype. We have identified a large consanguineous Saudi family segregating developmental delay, intellectual disability, epilepsy, high forehead and macrocephaly. Exome sequencing was performed in affected siblings of the family to study the novel mutation. Whole exome sequencing data analysis, confirmed by subsequent Sanger sequencing validation study. Our results showed a novel homozygous mutation (c.9368G>A) in a substitution of a conserved glycine residue into a glutamic acid in the exon 67 of SZT2 gene. The mutation was ruled out in 100 unrelated healthy controls. The missense variant has not yet been reported as pathogenic in literature or variant databases. In conclusion, the here detected homozygous SZT2 variant might be the causative mutation that further explain epilepsy and developmental delay in this Saudi family.