Identification of cystic fibrosis transmembrane conductance regulator gene (CFTR) variants: A retrospective study on the western and southern regions of Saudi Arabia.

OBJECTIVES: To investigate the geographic distribution of common cystic fibrosis (CF) variants in the western and southern regions of Saudi Arabia. METHODS: A retrospective study was conducted on 69 patients diagnosed with CF at King Faisal Specialist Hospital & Research Center, Jeddah. Patient data were collected retrospectively between June 2000 and November 2021. Various parameters were considered, including patient demographic information, CFTR variants, and respiratory cultures. RESULTS: We identified 26 CFTR variants in 69 patients with CF, including one novel variant that had not been reported or published before (1549del G) in 2 patients with CF. The 6 most prevalentvariants were as follows: c.1521_1523delCTT (19%), c.1418delG (10.2%), c.579+1G>T (8.8%), c.2988+1G>A (8.8%), c.3419 T>A (7.2%), and c.4124A>C (5.8%). In addition, respiratory cultures revealed that Pseudomonas aeruginosa, Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae were highly common among patients with CF. CONCLUSION: This study highlighted features of patients with CF residing in the Western and Southern regions of Saudi Arabia. Six of the 26 CFTR variants were common in these patients. We also report, for the first time, a novel variant and other CFTR variants that are yet to be reported in Saudi Arabia. These findings could help establish a foundation for cystic fibrosis screening in Saudi Arabia and may assist in clinical diagnosis and prognosis.

Severe asthma in children: An official statement from Saudi Pediatric Pulmonology Association.

In Saudi Arabia, the prevalence of pediatric asthma ranges between 8% and 25%. However, there are no sufficient data regarding severe asthma in childhood in Saudi Arabia. Therefore, a task force has been formed by the Saudi Pediatric Pulmonology Association which is a subsidiary group of the Saudi Thoracic Society and consists of Saudi experts with well-respected academic and clinical backgrounds in the fields of pediatric asthma as well as other respiratory diseases to write a consensus on definitions, phenotypes, and pathophysiology, evaluation, and management. To achieve this, the subject was divided into various sections, each of which was assigned to at least 2 experts. Without a central literature review, the authors searched the literature using their own strategies. To reach an agreement, the entire panel reviewed and voted on proposed findings and recommendations.

Combining RSPH9 founder mutation screening and next-generation sequencing analysis is efficient for primary ciliary dyskinesia diagnosis in Saudi patients.

Primary ciliary dyskinesia (PCD) is a clinically and genetically heterogeneous ciliopathy. Dysfunction of motile respiratory and nodal cilia results in sinopulmonary symptoms associated with laterality defects (LD) found in half of the patients. The molecular basis of the disease is insufficiently investigated in patients originating from the Arabian Peninsula. In a group of 16 unrelated Saudi patients clinically suspected of PCD and among whom only 5 (31%) had LD, we first screened by PCR-RFLP two founder mutations, RSPH9 c.804_806del and CCDC39 c.2190del previously identified in patients from the Arabian Peninsula and Tunisia, respectively. When negative, targeted panel or whole-exome sequencing was performed. Three patients were homozygous for the mutation in RSPH9, which encodes an axonemal protein that is absent from nodal cilia. None of the patients carried the CCDC39 founder mutation frequent in Tunisia. NGS analysis showed that nine patients had homozygous mutations in PCD genes. In total, sequential RFLP and NGS analysis solved 75% (12/16) of cases and identified ten distinct mutations, among which six are novel, in nine different genes. These results, which highlight the genetic heterogeneity of PCD in Saudi Arabia, show that the RSPH9 c.804_806del mutation is a prevalent mutation among Saudi patients, whereas the CCDC39 c.2190del ancestral allele is most likely related to the Berber population. This study shows that RSPH9 founder mutation first-line screening and NGS analysis is efficient for the genetic exploration of PCD in Saudi patients. The RSPH9 founder mutation accounts for the low rate of LD among Saudi patients.

A single-centre study of genetic mutations, audiology, echocardiogram and pulmonary function in Saudi children with osteogenesis imperfecta.

OBJECTIVES: Osteogenesis imperfecta (OI) is a heterogeneous group of inherited connective tissue disorders, characterised by skeletal fragility. Patients with OI may also exhibit extra-skeletal features like blue or grey scleral colour, fragile skin, easy bruising, joint laxity, short stature, deafness, cardiac valve abnormalities and abnormal pulmonary function. The objective of this study is to describe genetic mutations, prevalence of hearing issues, cardiac complications and impaired pulmonary function in children with OI. METHODS: This is a cross-sectional study of 23 Saudi children aged 6 months to 18 years who were diagnosed with OI. The revised Sillence classification (2,105) was used to classify the OI type. Whole exome sequencing was performed for genetic mutations. The hearing was assessed by either pure-tone audiometry and/or otoacoustic emission testing. Cardiac defects were screened by echocardiograms. Spirometry was performed to assess pulmonary function. Data were analysed with descriptive statistics. RESULTS: Based on the Sillence classification, 16 patients had OI type III, 6 had type IV and 1 had type I. Of the18 patients who had genetic sequencing, 66.6% had autosomal dominant and 33.3% had autosomal recessive mutations. Among children who had screening, hearing loss was diagnosed in 53% (9/17), congenital cardiac malformations in 26% (5/19) and restrictive lung disease in 70% (7/10). CONCLUSIONS: We found significant extra-skeletal features and a high yield of genetic mutations associated with OI. We suggest further studies to develop a screening protocol for extra-skeletal features in children with OI.

Geographic distribution of cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations in Saudi Arabia.

INTRODUCTION: Cystic fibrosis (CF) has been reported before in Saudi Arabia and the Gulf area. It has been found that screening for 10 most common cystic fibrosis transmembrane conductance regulator (CFTR) mutations can detect 80% of positive CFTR cases. OBJECTIVES: To determine the geographic distribution of the most common CFTR variants in 5 regions of Saudi Arabia. METHODOLOGY: A retrospective chart review of all CFTR variants conducted from January 1, 1992 to December 1, 2017. RESULTS: The ten most common CFTR mutations in the Saudi population were as follows: p.Gly473GlufsX54 (17%), p.Phe508del (12%), p.Ile1234Val (12%), 3120+1G > A (11%), 711+1G > T (9%), p.His139Leu (6%), p.Gln637Hisfs (5%), p.Ser549Arg (3%), p.N1303K (3%), and delExon19-21 (2%) along with other variants 79 (20%). In terms of the highest frequency, the c.2988+1G > A (3120+1G > A) variant was found in the eastern province (7.3%) of Saudi Arabia, the c.1418delG (p.Gly473GlufsX54) variant in the northern province (6.8%), the c.579+1G > T (711+1G > T) variant in the southern province (4.8%), the c.3700A > G (p.Ile1234Val) variant in the central province (4.8%), and c.1521_1523delCTT (p.Phe508del) variant in the western province (4.3%). CONCLUSION: The eastern and the northern provinces have the highest prevalence of CF, with the c.2988+1G > A (3120+1G > A) and c.1418delG (p.Gly473GlufsX54) variants showing the highest distribution in the Saudi CF population, which may reflect the effect of consanguinity within the same tribe. Proper family screening and counseling should be emphasized.

Childhood Asthma Awareness in Saudi Arabia: Five-Year Follow-Up Study.

BACKGROUND: Bronchial asthma is a chronic inflammatory airway disease that is characterized by reversible airway obstruction due to bronchial hyperresponsiveness. It is one of the most common chronic diseases. In Saudi Arabia, asthma affects 2 million people with asthma frequency in children markedly higher than adults with regional variations ranging from 9% to 33.7%. OBJECTIVE: The aim of this study is to measure asthma awareness and knowledge of study participants during the ongoing annual Saudi asthma awareness campaigns and compare them with previous survey data conducted in 2014. METHODS: A cross-sectional study was carried out in the form of a survey distributed across three major cities in Saudi Arabia, Jeddah, Riyadh and Dammam, during the National Asthma Awareness Campaign in major regional shopping centers in April 2019. Asthma knowledge scores across different demographic groups were generated from surveyed data. Descriptive and correlative statistical analyses were performed to identify factors associated with changes in asthma knowledge. Scores were compared to previous survey results. RESULTS: The mean score for asthma knowledge was 15.6 out of 25. Asthma knowledge significantly correlated with age (P=0.002), asthma status of the participants (P=0.001), having children with asthma (P=0.005) or knowing friends or family with asthma (P=0.029) but not with other socioeconomic factors such as gender, marital status, occupation, level of education and number of children in the family (P > 0.05). There was a significant difference in the asthma scores from 2014 (M= 63%, SD=26) to 2019 (M= 70%, SD= 26) conditions; t (24) = -2.106, p=0.046. CONCLUSION: Further educational campaigns are necessary to enhance and measure general public awareness of asthma, its differential diagnosis against other respiratory infections, environmental triggers, risk factors as well as treatment options.

Cystic fibrosis gene mutations and polymorphisms in Saudi men with infertility.

BACKGROUND: Some mutations of the cystic fibrosis transmembrane regulator (CFTR) gene may impair spermatogenesis or cause a congenital absence of the vas deferens that manifests as isolated male infertility. OBJECTIVE: Assess the frequency and analyze the spectrum of CFTR gene variations in Saudi men with primary infertility. DESIGN: Prospective, cross-sectional. SETTING: Tertiary care specialist hospital in Jeddah. PATIENTS AND METHODS: Genomic DNA was extracted from peripheral blood samples of Saudi men who presented with primary infertility to the outpatient andrology clinic with either azoospermia or oligoasthenoteratozoospermia. Polymerase chain reaction and direct sequencing were used to identify all variants of the CFTR gene. MAIN OUTCOME MEASURES: Proportion of the patients with a mutant CFTR gene and the spectrum of CFTR gene variations. SAMPLE SIZE: 50 infertile Saudi men. RESULTS: This study identified 10 CFTR gene variants in 7 (14%) subjects (100 chromosomes). The detected variants and polymorphisms were: c.1408G>A, c.4389G>A, c.2562T>G, c.869+11C>T, c.2909-92G>A, c.3469-65C>A, c.1210-6delT, c.1210-6T>A, c.2988+1G>A, and c.1210-13GT>TG. CONCLUSION: We demonstrated that 14% of the study subjects had one or more CFTR mutations and these were compounded in most of the affected patients. The spectrum of CFTR gene mutations in these subjects was similar to the mutations reported in other studies throughout the world. LIMITATIONS: Small sample size and the lack of a control group. CONFLICTS OF INTEREST: None.

Genotype patterns for mutations of the cystic fibrosis transmembrane conductance regulator gene: a retrospective descriptive study from Saudi Arabia.

BACKGROUND: Cystic fibrosis (CF) occurs in populations in Saudi Arabia and the Gulf area. Approximately 2000 known variants have been identified for the CF transmembrane conductance regulator (CTFR) gene. Screening for ten of the most common variants can detect 80% of alleles. OBJECTIVE: Determine the pattern of CFTR variants in the CF population of Saudi Arabia. DESIGN: A retrospective, descriptive. SETTING: Tertiary care center. PATIENTS AND METHODS: We examined the medical records of 396 confirmed CF patients of all age groups that were positive for a CFTR variant from the period of 1 January 1998 to 1 December 2017. MAIN OUTCOME MEASURES: Zygosity, morbidity and mortality patterns of different types of CFTR variants. SAMPLE SIZE: 312 families that included 396 patients. RESULTS: Of 48 variants identified, 6 were novel, having not been described in the medical literature. A homozygous state was found in 283 families (90.7%) and compound heterozygosity in 23 (7.4%). Six families were heterozygous (1.9%). Median age (interquartile range) was 10.2 months (4.4 months to 5.7 years) at diagnosis and 9.7 (5.4-16.5) years at follow up. Of 396 patients, 378 patients (95.5%) survived and 18 (4.5%) died. The ten most common variants identified in descending frequency were: p.Gly473GlufsX54 in 98 alleles (16%), p.Ile1234Val in 66 alleles (11%), F508del in 64 alleles (11%), 711+1G>T in 62 alleles (10%), 3120+1G>A in 62 alleles (11%), p.His139Leuin 38 alleles (6.4%), p.Gln637Hisfs in 30 alleles (5.2%), p.Ser549Arg in 27 alleles (4.5%), p.Asn1303Lys in 14 alleles (2.3%), delExon19-21in 10 alleles (1.6%). This analysis identified 79.2% of our CFTR variants. CONCLUSION: CFTR mutational patterns in our CF population are characterized by a high allelic heterogeneity. The high prevalence of homozygous variants reflects the high level of consanguinity between parents. LIMITATIONS: Our CFTR screening reflected only about 80% of CF patients in Saudi Arabia. CONFLICT OF INTEREST: None.