Shared genetic risk between major orofacial cleft phenotypes in an African population.

Nonsyndromic orofacial clefts (NSOFCs) represent a large proportion (70%-80%) of all OFCs. They can be broadly categorized into nonsyndromic cleft lip with or without cleft palate (NSCL/P) and nonsyndromic cleft palate only (NSCPO). Although NSCL/P and NSCPO are considered etiologically distinct, recent evidence suggests the presence of shared genetic risks. Thus, we investigated the genetic overlap between NSCL/P and NSCPO using African genome-wide association study (GWAS) data on NSOFCs. These data consist of 814 NSCL/P, 205 NSCPO cases, and 2159 unrelated controls. We generated common single-nucleotide variants (SNVs) association summary statistics separately for each phenotype (NSCL/P and NSCPO) under an additive genetic model. Subsequently, we employed the pleiotropic analysis under the composite null (PLACO) method to test for genetic overlap. Our analysis identified two loci with genome-wide significance (rs181737795 [p = 2.58E-08] and rs2221169 [p = 4.5E-08]) and one locus with marginal significance (rs187523265 [p = 5.22E-08]). Using mouse transcriptomics data and information from genetic phenotype databases, we identified MDN1, MAP3k7, KMT2A, ARCN1, and VADC2 as top candidate genes for the associated SNVs. These findings enhance our understanding of genetic variants associated with NSOFCs and identify potential candidate genes for further exploration.

Rare Variants Analyses Suggest Novel Cleft Genes in the African Population.

Non-syndromic orofacial clefts (NSOFCs) are common birth defects with a complex etiology. While over 60 common risk loci have been identified, they explain only a small proportion of the heritability for NSOFC. Rare variants have been implicated in the missing heritability. Thus, our study aimed to identify genes enriched with nonsynonymous rare coding variants associated with NSOFCs. Our sample included 814 non-syndromic cleft lip with or without palate (NSCL/P), 205 non-syndromic cleft palate only (NSCPO), and 2150 unrelated control children from Nigeria, Ghana, and Ethiopia. We conducted a gene-based analysis separately for each phenotype using three rare-variants collapsing models: (1) protein-altering (PA), (2) missense variants only (MO); and (3) loss of function variants only (LOFO). Subsequently, we utilized relevant transcriptomics data to evaluate associated gene expression and examined their mutation constraint using the gnomeAD database. In total, 13 genes showed suggestive associations (p = E-04). Among them, eight genes (ABCB1, ALKBH8, CENPF, CSAD, EXPH5, PDZD8, SLC16A9, and TTC28) were consistently expressed in relevant mouse and human craniofacial tissues during the formation of the face, and three genes (ABCB1, TTC28, and PDZD8) showed statistically significant mutation constraint. These findings underscore the role of rare variants in identifying candidate genes for NSOFCs.

Perceptions and beliefs of community gatekeepers about genomic risk information in African cleft research.

BACKGROUND: A fundamental ethical issue in African genomics research is how socio-cultural factors impact perspectives, acceptance, and utility of genomic information, especially in stigmatizing conditions like orofacial clefts (OFCs). Previous research has shown that gatekeepers (e.g., religious, political, family or community leaders) wield considerable influence on the decision-making capabilities of their members, including health issues. Thus, their perspectives can inform the design of engagement strategies and increase exposure to the benefits of genomics testing/research. This is especially important for Africans underrepresented in genomic research. Our study aims to investigate the perspectives of gatekeepers concerning genomic risk information (GRI) in the presence of OFCs in a sub-Saharan African cohort. METHODS: Twenty-five focus group discussions (FGDs) consisting of 214 gatekeepers (religious, community, ethnic leaders, and traditional birth attendants) in Lagos, Nigeria, explored the opinions of participants on genomic risk information (GRI), OFC experience, and the possibility of involvement in collaborative decision-making in Lagos, Nigeria. Transcripts generated from audio recordings were coded and analyzed in NVivo using thematic analysis. RESULTS: Three main themes-knowledge, beliefs, and willingness to act-emerged from exploring the perspective of gatekeepers about GRI in this group. We observed mixed opinions regarding the acceptance of GRI. Many participants believed their role is to guide and support members when they receive results; this is based on the level of trust their members have in them. However, participants felt they would need to be trained by medical experts to do this. Also, religious and cultural beliefs were crucial to determining participants' understanding of OFCs and the acceptance and utilization of GRI. CONCLUSIONS: Incorporating cultural sensitivity into public engagement could help develop appropriate strategies to manage conflicting ideologies surrounding genomic information in African communities. This will allow for more widespread access to the advances in genomics research in underrepresented populations. We also recommend a synergistic relationship between community health specialists/scientists, and community leaders, including spiritual providers to better understand and utilize GRI.

Parents and Provider Perspectives on the Return of Genomic Findings for Cleft Families in Africa.

BACKGROUND: Inadequate knowledge among health care providers (HCPs) and parents of affected children limits the understanding and utility of secondary genetic findings (SFs) in under-represented populations in genomics research. SFs arise from deep DNA sequencing done for research or diagnostic purposes and may burden patients and their families despite their potential health importance. This study aims to evaluate the perspective of both groups regarding SFs and their choices in the return of results from genetic testing in the context of orofacial clefts. METHODS: Using an online survey, we evaluated the experiences of 252 HCPs and 197 parents across participating cleft clinics in Ghana and Nigeria toward the return of SFs across several domains. RESULTS: Only 1.6% of the HCPs felt they had an expert understanding of when and how to incorporate genomic medicine into practice, while 50.0% agreed that all SFs should be returned to patients. About 95.4% of parents were willing to receive all the information from genetic testing (including SFs), while the majority cited physicians as their primary information source (64%). CONCLUSIONS: Overall, parents and providers were aware that genetic testing could help in the clinical management of diseases. However, they cited a lack of knowledge about genomic medicine, uncertain clinical utility, and lack of available learning resources as barriers. The knowledge gained from this study will assist with developing guidelines and policies to guide providers on the return of SFs in sub-Saharan Africa and across the continent.

Clinically actionable secondary findings in 130 triads from sub-Saharan African families with non-syndromic orofacial clefts.

INTRODUCTION: The frequency and implications of secondary findings (SFs) from genomic testing data have been extensively researched. However, little is known about the frequency or reporting of SFs in Africans, who are underrepresented in large-scale population genomic studies. The availability of data from the first whole-genome sequencing for orofacial clefts in an African population motivated this investigation. METHODS: In total, 130 case-parent trios were analyzed for SFs within the ACMG SFv.3.0 list genes. Additionally, we filtered for four more genes (HBB, HSD32B, G6PD and ACADM). RESULTS: We identified 246 unique variants in 55 genes; five variants in four genes were classified as pathogenic or likely pathogenic (P/LP). The P/LP variants were seen in 2.3% (9/390) of the subjects, a frequency higher than ~1% reported for diverse ethnicities. On the ACMG list, pathogenic variants were observed in PRKAG (p. Glu183Lys). Variants in the PALB2 (p. Glu159Ter), RYR1 (p. Arg2163Leu) and LDLR (p. Asn564Ser) genes were predicted to be LP. CONCLUSION: This study provides information on the frequency and pathogenicity of SFs in an African cohort. Early risk detection will help reduce disease burden and contribute to efforts to increase knowledge of the distribution and impact of actionable genomic variants in diverse populations.

Adapting Elements of Cleft Care Protocols in Low- and Middle-income Countries During and After COVID-19: A Process-driven Review With Recommendations.

A consortium of global cleft professionals, predominantly from low- and middle-income countries, identified adaptations to cleft care protocols during and after COVID-19 as a priority learning area of need.A multidisciplinary international working group met on a videoconferencing platform in a multi-staged process to make consensus recommendations for adaptations to cleft protocols within resource-constrained settings. Feedback was sought from a roundtable discussion forum and global organizations involved in comprehensive cleft care.Foundational principles were agreed to enable recommendations to be globally relevant and two areas of focus within the specified topic were identified. First the safety aspects of cleft surgery protocols were scrutinized and COVID-19 adaptations, specifically in the pre- and perioperative periods, were highlighted. Second, surgical procedures and cleft care services were prioritized according to their relationship to functional outcomes and time-sensitivity. The surgical procedures assigned the highest priority were emergent interventions for breathing and nutritional requirements and primary palatoplasty. The cleft care services assigned the highest priority were new-born assessments, pediatric support for children with syndromes, management of acute dental or auditory infections and speech pathology intervention.A collaborative, interdisciplinary and international working group delivered consensus recommendations to assist with the provision of cleft care in low- and middle-income countries. At a time of global cleft care delays due to COVID-19, a united approach amongst global cleft care providers will be advantageous to advocate for children born with cleft lip and palate in resource-constrained settings.

Damaging Mutations in AFDN Contribute to Risk of Nonsyndromic Cleft Lip With or Without Cleft Palate.

Novel or rare damaging mutations have been implicated in the developmental pathogenesis of nonsyndromic cleft lip with or without cleft palate (nsCL ± P). Thus, we investigated the human genome for high-impact mutations that could explain the risk of nsCL ± P in our cohorts.We conducted next-generation sequencing (NGS) analysis of 130 nsCL ± P case-parent African trios to identify pathogenic variants that contribute to the risk of clefting. We replicated this analysis using whole-exome sequence data from a Brazilian nsCL ± P cohort. Computational analyses were then used to predict the mechanism by which these variants could result in increased risks for nsCL ± P.We discovered damaging mutations within the AFDN gene, a cell adhesion molecule (CAMs) that was previously shown to contribute to cleft palate in mice. These mutations include p.Met1164Ile, p.Thr453Asn, p.Pro1638Ala, p.Arg669Gln, p.Ala1717Val, and p.Arg1596His. We also discovered a novel splicing p.Leu1588Leu mutation in this protein. Computational analysis suggests that these amino acid changes affect the interactions with other cleft-associated genes including nectins (PVRL1, PVRL2, PVRL3, and PVRL4) CDH1, CTNNA1, and CTNND1.This is the first report on the contribution of AFDN to the risk for nsCL ± P in humans. AFDN encodes AFADIN, an important CAM that forms calcium-independent complexes with nectins 1 and 4 (encoded by the genes PVRL1 and PVRL4). This discovery shows the power of NGS analysis of multiethnic cleft samples in combination with a computational approach in the understanding of the pathogenesis of nsCL ± P.

Investigating the relationship between cancer and orofacial clefts using GWAS significant loci for cancers: A case-control and case-triad study.

Background: Several population-based case-control studies have reported concurrent presentation of cancer and congenital malformations. Many associations have been made between oral clefting and cancers, though some of these results are conflicting. Some studies have reported an increased risk of cancer among 1st-degree relatives of cleft cases and vice versa, and also an excess risk of cancers of the breast, lung, and brain among those with oral clefts. This study aimed to determine if the genetic polymorphisms found in some cancers are also associated with orofacial cleft in an African cohort. Methods: The study was a case-control and case-triad study in which cases were 400 individuals clinically diagnosed with non-syndromic cleft lip and/or palate (CL/P), while controls were 450 individuals without CL/P. Samples were obtained from three African countries while DNA extraction, PCR, and genotyping were carried out at the University of Iowa, US. Eleven SNPs in genes coding for SWI/SNF subunits and 13 GWAS significant SNPs for cancers associated with orofacial cleft were selected. Case-control analysis, transmission disequilibrium test (TDT), and DFAM to combine the parent-offspring trio data and unrelated case/control data in a single analysis were carried out using PLINK. Results: For the case-control analyses that included all the clefts and for the CLP subtype, none of the SNPs were statistically significant. Statistically increased risk for the following SNPs rs34775372 (p = 0.02; OR = 1.54, CI:1.07-2.22), rs55658222 (p = 0.009; OR = 2.64, CI:1.28-5.45) and rs72728755 (p = 0.02; OR=2.27, CI:1.17-4.45) was observed with the CL only sub-group. None of these were significant after Bonferoni correction. In the TDT analyses, a significantly reduced risk with rs10941679 (p = 0.003; OR = 0.43, CI:0.24-0.75) was observed and this was significant after Bonferroni correction. The rs10941679 was also significant (p = 0.003) in the DFAM analyses as well even after Bonferroni correction. Conclusion: The results from this study represent an important starting point for understanding the concurrent presentation of some cancers in orofacial clefts, and cancer risks in cleft patients. The associations observed warrant further investigation in a larger cohort and will set the stage for a more mechanistic approach toward understanding the risk for cancers in families with clefts.

Patient-Proxy and Societal Perspectives of Quality-of-Life Utilities in Children With Cleft Lip and Palate Managed With Surgical Repair vs No Repair in Ethiopia.

Importance: In Ethiopia, more than 70% of infants with cleft lip and/or palate (CL/P) lack access to surgery. Infants who are untreated can experience severe malnutrition and extreme social stigma resulting in abandonment. Utilities are standardized measures of health-related quality of life (HRQOL) that inform health care resource allocation. However, CL/P utilities are missing from low- and middle-income countries (LMICs). Objective: To elicit utilities for untreated and surgically treated children with CL/P with consideration for social determinants of health from patient-proxy and societal participants. Design, Setting, and Participants: This cross-sectional study used patient proxies and societal participants in Addis Ababa, Ethiopia, from July 1, 2019, to January 30, 2020. Eligible patient proxies were caregivers of children younger than 18 years with nonsyndromic CL/P who were untreated or received surgery. Proxies were necessary as most patients were 0 to 4 years old and cannot reliably self-report. Eligible societal participants were 18 years and older with no family history of CL/P. Exposures: Surgical treatment and social determinants of health. Main Outcomes and Measures: Participants measured utilities using the visual analog scale (VAS), time trade-off (TTO), and standard gamble (SG). Results: In this study, 312 patient proxies and 135 societal participants were recruited. Mean (SD) utilities for untreated CL/P ranged from 0.57 (0.23) to 0.70 (0.22) from patient proxies and from 0.35 (0.21) to 0.8 (0.23) from societal participants, depending on utility instrument and cleft type. Surgical treatment was associated with a better HRQOL from the patient-proxy perspective (VAS, 0.17; 95% CI, 0.09 to 0.26; TTO, 0.15; 95% CI, 0.05 to 0.25) from the societal perspective (VAS, 0.21; 95% CI, 0.16 to 0.26; TTO, 0.17; 95% CI, 0.13 to 0.22; SG, 0.11; 95% CI, 0.06 to 0.15). Social determinants of health that were associated with patient-proxy utilities were income above the national mean (VAS, 0.10; 95% CI, 0.02 to 0.17; TTO, 0.11; 95% CI, 0.02 to 0.20), and religion (Christian vs other: TTO, -0.10; 95% CI, -0.17 to -0.03). From the societal perspective, the association between treatment and utilities was smaller in females compared with males (TTO, -0.05; 95% CI, -0.10 to -0.01). Conclusions and Relevance: The findings of this study suggest that CL/P disease severity and surgical impact in Ethiopia were undervalued by previous estimates from high-income countries and were associated with social determinants of health. Utility studies from participants from LMICs are feasible and necessary for representing HRQOL in LMICs and addressing health inequalities.

Whole-genome sequencing reveals de-novo mutations associated with nonsyndromic cleft lip/palate.

The majority (85%) of nonsyndromic cleft lip with or without cleft palate (nsCL/P) cases occur sporadically, suggesting a role for de novo mutations (DNMs) in the etiology of nsCL/P. To identify high impact protein-altering DNMs that contribute to the risk of nsCL/P, we conducted whole-genome sequencing (WGS) analyses in 130 African case-parent trios (affected probands and unaffected parents). We identified 162 high confidence protein-altering DNMs some of which are based on available evidence, contribute to the risk of nsCL/P. These include novel protein-truncating DNMs in the ACTL6A, ARHGAP10, MINK1, TMEM5 and TTN genes; as well as missense variants in ACAN, DHRS3, DLX6, EPHB2, FKBP10, KMT2D, RECQL4, SEMA3C, SEMA4D, SHH, TP63, and TULP4. Many of these protein-altering DNMs were predicted to be pathogenic. Analysis using mouse transcriptomics data showed that some of these genes are expressed during the development of primary and secondary palate. Gene-set enrichment analysis of the protein-altering DNMs identified palatal development and neural crest migration among the few processes that were significantly enriched. These processes are directly involved in the etiopathogenesis of clefting. The analysis of the coding sequence in the WGS data provides more evidence of the opportunity for novel findings in the African genome.

Outcomes of microsurgical free tissue transfer performed on international surgical collaborations in low-income and middle-income countries: A systematic review and meta-analysis.

BACKGROUND: Microsurgical free tissue transfer is the gold standard for reconstruction of significant soft tissue and bony defects following cancer resection and trauma. Many reconstructive units in low-income and middle-income countries (LMICs) do not yet have access to the resources or training required to perform microsurgical procedures. Long-term international collaborations have been formed with annual reconstructive programmes conducting microsurgery. AIMS: To critically analyze outcomes of microsurgical free tissue transfer performed on international reconstructive collaborations in LMICs. METHODS: PRISMA-compliant systematic review and meta-analysis of outcomes for free tissue transfer performed during international collaborations in LMICs using an inverse variance model. The study protocol was published prospectively and registered with PROSPERO (ID: CRD42021225613). RESULTS: Seven studies, included 290 flaps on 284 patients. The most common sites requiring reconstruction were Head and neck (53% (n = 153)) and lower limb (7.9% (n = 23)) were lower limb reconstruction. The most common free flaps were radial forearm (22%; n = 64) and anterolateral thigh (18%; n = 51). Total Flap Failure rate was 3.8% (n = 13; 95% confidence interval (CI) = 1.9-6.3%) Overall complication rate was 38% (95% CI =27-48%), with 19% of flaps requiring emergency return to theatre (95% CI =14-26%). Flap salvage was successful in 52% of take-backs (95% CI =15% - 88%). CONCLUSIONS: Free flaps performed during international surgical collaborations in LMICs have comparable failure rates to those performed in higher-income settings. However, there are higher complication and take-back rates. This should be taken into account when planning international collaborations. These results should help preoperative counselling and the consent process.

Variant analyses of candidate genes in orofacial clefts in multi-ethnic populations.

OBJECTIVES: Cleft lip with/without cleft palate and cleft palate only is congenital birth defects where the upper lip and/or palate fail to fuse properly during embryonic facial development. Affecting ~1.2/1000 live births worldwide, these orofacial clefts impose significant social and financial burdens on affected individuals and their families. Orofacial clefts have a complex etiology resulting from genetic variants combined with environmental covariates. Recent genome-wide association studies and whole-exome sequencing for orofacial clefts identified significant genetic associations and variants in several genes. Of these, we investigated the role of common/rare variants in SHH, RORA, MRPL53, ACVR1, and GDF11. MATERIALS AND METHODS: We sequenced these five genes in 1255 multi-ethnic cleft lip with/without palate and cleft palate only samples in order to find variants that may provide potential explanations for the missing heritability of orofacial clefts. Rare and novel variants were further analyzed using in silico predictive tools. RESULTS: Ninteen total variants of interest were found, with variant types including stop-gain, missense, synonymous, intronic, and splice-site variants. Of these, 3 novel missense variants were found, one in SHH, one in RORA, and one in GDF11. CONCLUSION: This study provides evidence that variants in SHH, RORA, MRPL53, ACVR1, and GDF11 may contribute to risk of orofacial clefts in various populations.

Genome-Wide Scan for Parent-of-Origin Effects in a sub-Saharan African Cohort With Nonsyndromic Cleft Lip and/or Cleft Palate (CL/P).

OBJECTIVE: Nonsyndromic cleft lip and/or cleft palate (NSCL/P) have multifactorial etiology where genetic factors, gene-environment interactions, stochastic factors, gene-gene interactions, and parent-of-origin effects (POEs) play cardinal roles. POEs arise when the parental origin of alleles differentially impacts the phenotype of the offspring. The aim of this study was to identify POEs that can increase risk for NSCL/P in humans using a genome-wide dataset. METHODS: The samples (174 case-parent trios from Ghana, Ethiopia, and Nigeria) included in this study were from the African only genome wide association studies (GWAS) that was published in 2019. Genotyping of individual DNA using over 2 million multiethnic and African ancestry-specific single-nucleotide polymorphisms from the Illumina Multi-Ethnic Genotyping Array v2 15070954 A2 (genome build GRCh37/hg19) was done at the Center for Inherited Diseases Research. After quality control checks, PLINK was employed to carry out POE analysis employing the pooled subphenotypes of NSCL/P. RESULTS: We observed possible hints of POEs at a cluster of genes at a 1 mega base pair window at the major histocompatibility complex class 1 locus on chromosome 6, as well as at other loci encompassing candidate genes such as ASB18, ANKEF1, AGAP1, GABRD, HHAT, CCT7, DNMT3A, EPHA7, FOXO3, lncRNAs, microRNA, antisense RNAs, ZNRD1, ZFAT, and ZBTB16. CONCLUSION: Findings from our study suggest that some loci may increase the risk for NSCL/P through POEs. Additional studies are required to confirm these suggestive loci in NSCL/P etiology.

Mutations in Van Der Woude Families From Ethiopia.

BACKGROUND: Van der Woude syndrome (VWS) is the most common syndromic orofacial cleft which accounts for approximately 2% of all cleft lip (CL) and/or palate cases. It is characterized by the presence of lower lip pits, in addition to CL, CL with or without cleft palate, cleft palate only, and hypodontia. It is inherited as an autosomal-dominant trait with almost complete penetrance but variable expressivity, and different variants in IRF6 gene have been reported in different populations around the world including African populations (Ethiopian, Ghanaian, and Nigerian). METHODS AND FINDINGS: The authors investigated the role of IRF6 in Ethiopian families with VWS. The DNA of 7 families with VWS from Ethiopia were screened by Sanger sequencing. The authors screened all 9 exons of IRF6 and found a novel missense variant in exon 4 (p. Gly65Glu). This variant was predicted to be deleterious/probably damaging by Sift and PolyPhen, respectively. The IRF6 variant (p. Gly65Glu) segregates in the family since it was identified in the father and a sibling. CONCLUSION: Several of the individuals with lower lip pits in this study did not seek treatment. This is due to lack of awareness about the significance of this minor looking deformity and its consequences, and availability of treatment for birth defects. Therefore, it is important to educate families. Finally, screening for novel variants in known genes has a role in counseling and prenatal diagnosis for high-risk families.

Assessing the Practice of Birth Defect Registration at Addis Ababa Health Facilities.

BACKGROUND: Birth defects are conditions that exist at birth and cause structural changes in one or more parts of the body. In order to plan proper management and design preventive activities of these conditions, accurate tracking, registration and analyses of the registered data are important. We assessed the practice of birth defect registration at Addis Ababa health facilities. METHODS: We retrospectively checked the existence of a separate birth defect registry book and assessed the delivery room registration book for completeness in registering birth defects. We also assessed the total number of birth defects registered during 2010-2015. RESULTS: We assessed the practice of birth defect registration at 37 delivery service providing health facilities in Addis Ababa, 20 public and 17 private institutions. Of the 37 health institutions assessed, 23 registered birth defects (3 of them used a separate birth defect registry books, and 20 used a regular registration book to register birth defects). The remaining 14 did not register any congenital anomaly. Of the institutions that do not register congenital anomalies, 10 are private and four are public. CONCLUSION: Only three delivery providing health facilities had a dedicated birth defect registry book which is close to ideal for a birth defect registration. There is a need for others to do the same until an electronic birth defect registration is established. This registration will serve as a resource for clinical governance and studies into quality of life, quality of care, etiology and prevention.

Protocol for a systematic review of outcomes from microsurgical free-tissue transfer performed on short-term collaborative surgical trips in low-income and middle-income countries.

BACKGROUND: In many units around the world, microsurgical free-tissue transfer represents the gold standard for reconstruction of significant soft tissue defects following cancer, trauma or infection. However, many reconstructive units in low-income and middle-income countries (LMICs) do not yet have access to the resources, infrastructure or training required to perform any microsurgical procedures. Long-term international collaborations have been formed with annual short-term reconstructive missions conducting microsurgery. In the first instance, these provide reconstructive surgery to those who need it. In the longer-term, they offer an opportunity for teaching and the development of sustainable local services. METHODS: A PRISMA-compliant systematic review and meta-analysis will be performed. A comprehensive, predetermined search strategy will be applied to the MEDLINE and Embase electronic databases from inception to August 2021. All clinical studies presenting sufficient data on free-tissue transfer performed on short-term collaborative surgical trips (STCSTs) in LMICs will be eligible for inclusion. The primary outcomes are rate of free flap failure, rate of emergency return to theatre for free flap salvage and successful salvage rate. The secondary outcomes include postoperative complications, cost effectiveness, impact on training, burden of disease, legacy and any functional or patient reported outcome measures. Screening of studies, data extraction and assessments of study quality and bias will be conducted by two authors. Individual study quality will be assessed according to the Oxford Evidence-based Medicine Scales of Evidence 2, and risk of bias using either the 'Revised Cochrane risk of bias tool for randomized trials' (Rob2), the 'Risk of bias in non-randomized studies of interventions' (ROBINS-I) tool, or the National Institute for Health Quality Assessment tool for Case Series. Overall strength of evidence will be assessed according to the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. DISCUSSION: To-date the outcomes of microsurgical procedures performed on STCSTs to LMICs are largely unknown. Improved education, funding and allocation of resources are needed to support surgeons in LMICs to perform free-tissue transfer. STCSTs provide a vehicle for sustainable collaboration and training. Disseminating microsurgical skills could improve the care received by patients living with reconstructive pathology in LMICs, but this is poorly established. This study sets out a robust protocol for a systematic review designed to critically analyse outcomes. SYSTEMATIC REVIEW REGISTRATION: PROSPERO 225613.

Pattern of Orofacial Clefts at A Tertiary Care Hospital in Ethiopia.

Background: Clefts of the lip and/or palate are the most common craniofacial birth defects. The worldwide birth prevalence is 1/700 live births. There are varying reports from Africa. This study investigated the patterns of orofacial clefts at a tertiary care hospital in Addis Ababa. Methods: A retrospective descriptive study was performed to assess the patterns of Orofacial clefts at the main cleft care center in Ethiopia. The Data of cleft patients operated at the main cleft care center in Ethiopia from January 2007 to April 2020 with the support of Smile Train was used for this study. Their demographic and clinical data was retrieved from the Smile Train data base and analyzed using Stata version 16. Results: A total of 1919 patients' data was retrieved, excluding 16 patients' data (.83%). The data of 1903 (99.17%) patients were enrolled in this study. Cleft lip and palate were found in 53.0% of the patients. Cleft lip only was found in 731 (38.4%) and cleft palate only in 166 (8.6%) patients. The commonest surgery performed was primary unilateral lip nose repair. Most patients were operated after the age of five years old. Conclusion: Many were operated after the age of five years, which is not in line with international recommendations. This needs improvement: establish more cleft care centers, distribute health care information and education.

Non-random distribution of deleterious mutations in the DNA and protein-binding domains of IRF6 are associated with Van Der Woude syndrome.

BACKGROUND: The development of the face occurs during the early days of intrauterine life by the formation of facial processes from the first Pharyngeal arch. Derangement in these well-organized fusion events results in Orofacial clefts (OFC). Van der Woude syndrome (VWS) is one of the most common causes of syndromic cleft lip and/or palate accounting for 2% of all cases. Mutations in the IRF6 gene account for 70% of cases with the majority of these mutations located in the DNA-binding (exon 3, 4) or protein-binding domains (exon 7-9). The current study was designed to update the list of IRF6 variants reported for VWS by compiling all the published mutations from 2013 to date as well as including the previously unreported VWS cases from Africa and Puerto Rico. METHODS: We used PubMed with the search terms; "Van der Woude syndrome," "Popliteal pterygium syndrome," "IRF6," and "Orofacial cleft" to identify eligible studies. We compiled the CADD score for all the mutations to determine the percentage of deleterious variants. RESULTS: Twenty-one new mutations were identified from nine papers. The majority of these mutations were in exon 4. Mutations in exon 3 and 4 had CADD scores between 20 and 30 and mutations in exon 7-9 had CADD scores between 30 and 40. The presence of higher CADD scores in the protein-binding domain (exon 7-9) further confirms the crucial role played by this domain in the function of IRF6. In the new cases, we identified five IRF6 mutations, three novel missense mutations (p.Phe36Tyr, p.Lys109Thr, and p.Gln438Leu), and two previously reported nonsense mutations (p.Ser424*and p.Arg250*). CONCLUSION: Mutations in the protein and DNA-binding domains of IRF6 ranked among the top 0.1% and 1% most deleterious genetic mutations, respectively. Overall, these findings expand the range of VWS mutations and are important for diagnostic and counseling purposes.

SPECC1L regulates palate development downstream of IRF6.

SPECC1L mutations have been identified in patients with rare atypical orofacial clefts and with syndromic cleft lip and/or palate (CL/P). These mutations cluster in the second coiled-coil and calponin homology domains of SPECC1L and severely affect the ability of SPECC1L to associate with microtubules. We previously showed that gene-trap knockout of Specc1l in mouse results in early embryonic lethality. We now present a truncation mutant mouse allele, Specc1lΔC510, that results in perinatal lethality. Specc1lΔC510/ΔC510 homozygotes showed abnormal palate rugae but did not show cleft palate. However, when crossed with a gene-trap allele, Specc1lcGT/ΔC510 compound heterozygotes showed a palate elevation delay with incompletely penetrant cleft palate. Specc1lcGT/ΔC510 embryos exhibit transient oral epithelial adhesions at E13.5, which may delay shelf elevation. Consistent with oral adhesions, we show periderm layer abnormalities, including ectopic apical expression of adherens junction markers, similar to Irf6 hypomorphic mutants and Arhgap29 heterozygotes. Indeed, SPECC1L expression is drastically reduced in Irf6 mutant palatal shelves. Finally, we wanted to determine if SPECC1L deficiency also contributed to non-syndromic (ns) CL/P. We sequenced 62 Caucasian, 89 Filipino, 90 Ethiopian, 90 Nigerian and 95 Japanese patients with nsCL/P and identified three rare coding variants (p.Ala86Thr, p.Met91Iso and p.Arg546Gln) in six individuals. These variants reside outside of SPECC1L coiled-coil domains and result in milder functional defects than variants associated with syndromic clefting. Together, our data indicate that palate elevation is sensitive to deficiency of SPECC1L dosage and function and that SPECC1L cytoskeletal protein functions downstream of IRF6 in palatogenesis.