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The aim of this article is to describe the first case of Hutchinson-Gilford Progeria Syndrome (HGPS) in Togo and review all Africans cases. Our patient was a 12.8-year-old Togolese boy followed in our unit till he was 15-year-old for HGPS. He was the only child of non-consanguineous parents. The phenotypic findings were craniofacial dysmorphy, dwarfism, lipodystrophy, diffusely scattered hyperpigmented foci, pyriform thorax, nail dystrophy, decreased joint mobility, and camptodactyly. He had characteristic facies with prominent forehead, prominent eyes, absent ear lobule, thin nasal skin, convex nasal profile, micrognathia, and crowded teeth. Radiologicals findings were bilateral coxa valga, pyriform thorax, and acro-osteolysis. We sequenced the entire coding region of LMNA gene, and mutation analysis revealed a heterozygous mutation c.1824C>T (p.Gly608Gly). Our patient is therefore the fifth African and the fourth with classical mutation, first of Western Africa, and second of (sub-Saharan) African black race. The recurrence of HGPS is low like the cause is neomutation or germinal mosaicism.

Introduction:Fanconi anemia (FA) is a rare inherited hematological disease due to a defect in the DNA repair pathway resulting in congenital abnormalities and high susceptibility to develop cancers. The cytogenetic analysis using alkylating agents is still a reference test to establish the diagnosis. Despite the genetic heterogeneity, the identification of the causal mutation is actually performed especially after the development of next generation sequencing (NGS). Methods:we report here nine Moroccan patients referred to the department of Medical Genetics for suspicion of FA. We realized a genetic consultation to establish a clinical record with biological data before carrying out the genetic analysis. Karyotyping with mitomycin was performed for all the probands before elaborating molecular study. We used massively parallel sequencing to analyse the three most frequent mutated genesFANCA,FANCC, andFANCG, representing 84% of all genes involved in FA. Results:all the patients showed hematological signs associated with at least one extra hematological congenital anomaly. The chromosomal breaks were significantly higher for the nine patients, compared to the controls. The molecular diagnosis was confirmed in 8 of the 9 families tested (88.8%) with 4 novel mutations. The next generation based sequencing identified 9 variations: 6 in theFANCAgene (66,6%), 3 in theFANCGgene (33,3%) and noFANCCvariation was found. Of those, 7 were homozygous and 2 were compounds heterozygous. Conclusion:to the best of our knowledge, this is the first molecular report of Moroccan patients with FA suggesting the predominance of two genes without any recurrent mutation. The molecular analysis ofFANCAandFANCGgenes should be offered first for all patients in Morocco.

Progeroid Syndromes (PS), including Hutchinson-Gilford Progeria Syndrome (HGPS, OMIM #176670), are premature and accelerated aging that clinically resemble some aspects of advancing physiological aging. Most classical HGPS patients carry a de novo point mutation within exon 11 of the LMNA gene encoding A-type Lamins. This mutation activates a cryptic splice site leading to the deletion of 50 amino acids at its carboxy-terminal domain, resulting in a truncated and permanently farnesylated Prelamin A called Prelamin A Δ50 or Progerin that accumulates in HGPS cell nuclei and is a hallmark of the disease. Some patients with PS carry other LMNA mutations affecting exon 11 splicing, leading to defects in nuclear A-type Lamins and are named “HGPS-like” patients. They also produce Progerin and/or other truncated Prelamin A isoforms (Δ35 and Δ90). We recently found that MG132, a proteasome inhibitor, induced progerin clearance in classical HGPS through autophagy activation and splicing regulation. Here, we show that MG132 induces aberrant prelamin A clearance and improves cellular phenotypes in HGPS-like patient cells. These results provide preclinical proof of principle for the use of a promising class of molecules toward a potential therapy for children with HGPS-like, who may therefore be eligible for inclusion in a therapeutic trial based on this approach, together with classical HGPS patients.

CHARGE syndrome is a rare genetic disorder mainly due to de novo and private truncating mutations of CHD7 gene. Here we report an intriguing hot spot of intronic mutations (c.5405-7G > A, c.5405-13G > A, c.5405-17G > A and c.5405-18C > A) located in CHD7 IVS25. Combining computational in silico analysis, experimental branch-point determination and in vitro minigene assays, our study explains this mutation hot spot by a particular genomic context, including the weakness of the IVS25 natural acceptor-site and an unconventional lariat sequence localized outside the common 40 bp upstream the acceptor splice site. For each of the mutations reported here, bioinformatic tools indicated a newly created 3’ splice site, of which the existence was confirmed using pSpliceExpress, an easy-to-use and reliable splicing reporter tool. Our study emphasizes the idea that combining these two complementary approaches could increase the efficiency of routine molecular diagnosis.

Jalili syndrome is a rare autosomal recessive genetic disease characterized by the association of amelogenesis imperfecta and cone-rod retinal dystrophy. This syndrome is caused by mutations in the CNNM4 gene. Different types of CNNM4 mutations have been reported; missense, nonsense, large deletions, single base insertion, and duplication. We used Sanger sequencing to analyze a large consanguineous family with three siblings affected with Jalili syndrome, suspected clinically after dental and ophthalmological examination. These patients are carrying a novel homozygous mutation in the splice site acceptor of intron 3 (c.1682-1G > C) in the CNNM4 gene. We compare the findings of the present family to those from literature, in order to further delineate Jalili syndrome.

Background The discovery of somatic mutations within the gene encoding calreticulin (CALR) in 2013 represented a major milestone in the molecular diagnosis of BCR-ABL negative myeloproliferative neoplasms (MPN). In fact, exome sequencing revealed that most patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF) lacking JAK2 or MPL mutations, harbor somatic insertion and/or deletion in exon 9 of CALR gene. In this study, we identified the first CALR gene mutational landscape in Moroccan patients with MPN nonmutated for the JAK2 gene. Methods We performed Sanger sequencing of exon 9 of CALR gene in blood samples obtained from 33 Moroccan patients with ET or PMF non-mutated for JAK2. Results Of the 33 patients analyzed, we detected eight distinct variants in 15 patients (45.4%); six indel mutations, five with type 1 recurrent 52 bp deletion, four with type 2 recurrent 5 bp insertion and one in frame deletion which was found to be a germline variant suggesting a very rare condition in MPN. Conclusion This is the first cohort reported in CALR gene mutation analysis in Morocco. Our results were concordant with studies reported up to date and very encouraging in promoting the molecular diagnosis of myeloproliferative neoplasms in Moroccan patients. Moreover, the presence of a germline in frame deletion in a symptomatic patient should undermine the effectiveness of sizing assays without DNA sequencing in the diagnosis of CALR mutations.

Background To date, a limited number of BRCA1/2 germline mutations have been reported in hereditary breast and/or ovarian cancer in the Moroccan population. Less than 20 different mutations of these two genes have been identified in Moroccan patients, and recently we reported a further BRCA2 mutation (c.1310_1313delAAGA; p.Lys437IlefsX22) in three unrelated patients, all from the North-East of the country. We aimed in this study to evaluate the frequency and geographic distribution of this BRCA2 frameshift mutation, in order to access its use as the first-line BRCA genetic testing strategy for Moroccan patients. We enrolled in this study 122 patients from different regions of Morocco, with suggestive inherited predisposition to breast and ovarian cancers. All subjects gave written informed consent to BRCA1/2 genetic testing. According to available resources of our lab and enrolled families, 51 patients were analyzed by the conventional individual exon-by-exon Sanger sequencing, 23 patients were able to benefit from a BRCA next generation sequencing and a target screening for exon 10 of BRCA2 gene was performed in 48 patients. Results Overall, and among the 122 patients analyzed for at least the exon 10 of the BRCA2 gene, the c.1310_1313delAAGA frameshift mutation was found in 14 patients. Genealogic investigation revealed that all carriers of this mutation shared the same geographic origin and were descendants of the North-East of Morocco. Discussion In this study, we highlighted that c.1310_1313delAAGA mutation of BRCA2 gene is recurrent with high frequency in patients from the North-East region of Morocco. Therefore, we propose to use, in public health strategies, the detection of this mutation as the first-line screening tests in patients with breast and ovarian cancer originated from this region.

Progeria, or Hutchinson-Gilford syndrome, is a rare genetic disease, characterized by several clinical features that develop in childhood, in particular, an accelerated aging aspect. Its incidence is 1-4 per 8 million newborns. Children with progeria syndrome usually appear normal at birth and in early infancy. Profound failure to thrive occurs during the 1st year. Characteristic facies, partial alopecia progressing to total alopecia, loss of subcutaneous fat, stiffness of joints, bone changes, and abnormal tightness of the skin over the abdomen and upper thighs usually become apparent during the 2nd to 3rd years. Motor and mental development is normal. Patients develop severe atherosclerosis. Death occurs as a result of complications of cardiac or cerebrovascular disease (heart attack or stroke) generally between ages 6 and 20 years. The diagnosis of Hutchinson-Gilford progeria syndrome (HGPS) is based on recognition of common clinical features and the detection of the recurrent p.Gly608Gly mutation in exon 11 of the LMNA gene, which is present in almost all individuals with HGPS. We present here 3 patients aged 5, 11, and 12 years referred to genetic consultation for dysmorphic facies and failure to thrive. After careful clinical examination and paraclinical assessment, the diagnosis of progeria syndrome was raised. We performed molecular analysis for the 3 patients by searching for the recurrent mutation c.1824C>T (p.Gly608Gly) of the LMNA gene, which was found only in 1 patient. We discuss the geneticist's role in the diagnosis of rare dysmorphic syndromes and their genetic counseling. We also analyze the clinical spectrum of HGPS by comparing the 3 patients.

Waardenburg syndrome (WS) is a neurocristopathy disorder combining sensorineural deafness and pigmentary abnormalities. The presence of additional signs defines the 4 subtypes. WS type IV, also called Shah-Waardenburg syndrome (SWS), is characterized by the association with congenital aganglionic megacolon (Hirschsprung disease). To date, 3 causative genes have been related to this congenital disorder. Mutations in the EDNRB and EDN3 genes are responsible for the autosomal recessive form of SWS, whereas SOX10 mutations are inherited in an autosomal dominant manner. We report here the case of a 3-month-old Morrocan girl with WS type IV, born to consanguineous parents. The patient had 3 cousins who died in infancy with the same symptoms. Molecular analysis by Sanger sequencing revealed the presence of a novel homozygous missense mutation c.1133A>G (p.Asn378Ser) in the EDNRB gene. The proband's parents as well as the parents of the deceased cousins are heterozygous carriers of this likely pathogenic mutation. This molecular diagnosis allows us to provide genetic counseling to the family and eventually propose prenatal diagnosis to prevent recurrence of the disease in subsequent pregnancies.

Xeroderma pigmentosum (XP) is an autosomal recessive inherited disease which is genetically heterogeneous. The prevalence of this genodermatosis is estimated to be 1/1 000 000 in the USA; it is more common in Japan and probably in other populations with high levels of consanguinity. The molecular diagnosis and identification of mutation in patients requires the knowledge of the causative gene by the determination of XP complementation groups. Soufir et al. have reported that XPC is the major disease-causing gene with a recurrent mutation in the Mediterranean region. The mutation c.1643_1644delTG (p.Val548AlafsX25) represents alone 74% of all the XP probands tested and 87% in XP type C in North African patients with founder effect. We used molecular epidemiological methods in the present study to calculate the frequency of heterozygote for this mutation in Moroccan newborns and estimate the prevalence of XP in the Moroccan population. DNA extracted from umbilical cord blood samples of 250 newborns were tested for the recurrent XPC mutation c.1643_1644delTG using real-time polymerase chain reaction. Heterozygotes profiles were confirmed by direct sequencing. Among 250 newborns tested, one subject was heterozygous for the mutation c.1643_1644delTG. The carrier frequency was estimated to be 1/250 which would imply that the prevalence of XP would be approximately 1/80 504 considering the effect of consanguinity. This is the first report of the prevalence of XP in an Arab country and it shows that the prevalence of xeroderma pigmentosum is higher than that found in Europe and the USA.

Xeroderma pigmentosum (XP) is an autosomal recessive inherited disease which is genetically heterogeneous. The prevalence of this genodermatosis is estimated to be 1/1 000 000 in the USA; it is more common in Japan and probably in other populations with high levels of consanguinity. The molecular diagnosis and identification of mutation in patients requires the knowledge of the causative gene by the determination of XP complementation groups. Soufir et al. have reported that XPC is the major disease-causing gene with a recurrent mutation in the Mediterranean region. The mutation c.1643_1644delTG (p.Val548AlafsX25) represents alone 74% of all the XP probands tested and 87% in XP type C in North African patients with founder effect. We used molecular epidemiological methods in the present study to calculate the frequency of heterozygote for this mutation in Moroccan newborns and estimate the prevalence of XP in the Moroccan population. DNA extracted from umbilical cord blood samples of 250 newborns were tested for the recurrent XPC mutation c.1643_1644delTG using real-time polymerase chain reaction. Heterozygotes profiles were confirmed by direct sequencing. Among 250 newborns tested, one subject was heterozygous for the mutation c.1643_1644delTG. The carrier frequency was estimated to be 1/250 which would imply that the prevalence of XP would be approximately 1/80 504 considering the effect of consanguinity. This is the first report of the prevalence of XP in an Arab country and it shows that the prevalence of xeroderma pigmentosum is higher than that found in Europe and the USA.

Hutchinson-Gilford Progeria syndrome (HGPS) is a rare genetic disorder, characterized by several clinical features that begin in early childhood, recalling an accelerated aging process. The diagnosis of HGPS is based on the recognition of common clinical features and detection of the recurrent heterozygous c.1824C>T (p.Gly608Gly) mutation within exon 11 in the Lamin A/C encoding gene (LMNA). Besides "typical HGPS," several "atypical progeria" syndromes (APS) have been described, in a clinical spectrum ranging from mandibuloacral dysplasia to atypical Werner syndrome. These patients's clinical features include progeroid manifestations, such as short stature, prominent nose, premature graying of hair, partial alopecia, skin atrophy, lipodystrophy, skeletal anomalies, such as mandibular hypoplasia and acroosteolyses, and in some cases severe atherosclerosis with metabolic complications. APS are due in several cases to de novo heterozygous LMNA mutations other than the p.Gly608Gly, or due to homozygous BAFN1 mutations in Nestor-Guillermo Progeria syndrome (NGPS). We report here and discuss the observation of a non-consanguineous Moroccan patient presenting with atypical progeria. The molecular studies showed the heterozygous mutation c.412G>A (p.Glu138Lys) of the LMNA gene. This mutation, previously reported as a de novo mutation, was inherited from the apparently healthy father who showed a somatic cell mosaicism.