Human leukocyte antigen immunization in transfusion-dependent Moroccan patients with beta-thalassemia major: prevalence and risk factors

INTRODUCTION

Beta-thalassemia major patients need a regular blood transfusion to have an initial normal growth. However, these patients have an increased risk of developing alloantibodies. Our main goal was to study HLA alloimmunization in Moroccan Beta-thalassemia patients by confronting it with transfusion and demographic criteria, exploring the involvement of HLA typing profile in the development of HLA antibodies and in turn determining risk factors for their development.

METHODS

The study consisted of 53 Moroccan pediatric patients with Beta-thalassemia major. Screening for HLA alloantibodies was performed using Luminex technology Whereas HLA genotyping was done with sequence-specific primers (PCR-SSP).

RESULTS

In this study, 50.9% of patients have been identified as positive for HLA antibodies, with 59.3% having both HLA Class I and Class II antibodies. A significant increase frequency of DRB1*11 allele was revealed in non-immunized patients (34.6% vs. 0%, p = 0.001). Our results also revealed that the majority of our HLA immunized patients were women (72.4% vs. 27.6%, p = 0.001), and transfused with more than 300 units of RBC units (66.7% vs. 33.3%, p = 0.02). There were statistically significant differences when comparing these frequencies.

CONCLUSIONS

This paper revealed that the transfusion dependent Beta-thalassemia major patients are exposed to risk of developing HLA antibodies following transfusions with leukoreduced RBC units. The HLA DRB1*11 was a protective factor against HLA alloimmunization in our beta-thalassemia major patients.

Collection, cryopreservation and thawing of stem cells for children weighing less than 25 Kg with high-risk neuroblastoma: A single center results in Morocco

Introduction

An important component of the advances made in neuroblastoma treatment has been the use of peripheral blood stem cells to support high-dose chemotherapy. In this study, we report our experience on a series of small children who have undergone standard and large volume leukaphersis (LVL) procedures, provide an update on a single institution's experience with cryopreservation of autologous peripheral blood stem cells (PBSCs), using 10% dimethyl sulfoxide (DMSO) and applying post-thaw DMSO depletion and analyze a number of variables that may affect viability.

Methods

A total of 36 aphereses were performed on 29 children weighing less than 25 kg between July 2016 and October 2019 at the Ibn Sina university hospital.

Results

Seven females and twenty-two males, median bodyweight 14 kg (9 - 22). A single apheresis was sufficient to obtain at least 3 × 10⁶/kg body weight (BW) of CD34+ cells in 82.8% of the cases. The LVL was performed in 22 aphereses. A median number of 5.9 × 10⁶/kg CD34 cells were collected per apheresis. A total of 60 PBSC samples were cryopreserved and 46 samples were infused. The mean cell viability percentage decreased from 94.75 ± 1.14% before freezing to 70.84 ± 8.6% after thawing (p < 0.001). No correlation was found between post-thaw viability and storage time (r = -0.233; p = 0.234) or number of total nucleated cells (r = 0.344; p = 0.073).

Conclusion

Leukapheresis is safe and feasible in small pediatric patients if the appropriate measures are used. Cryopreservation poses numerous challenges, especially a decrease in cell viability after thawing.

[Husband to wife renal transplantatation and pretransplant HLA immunization: about two cases]

La transplantation rénale est la meilleure thérapeutique pour l'insuffisance rénale terminale. Cette transplantation est possible grâce au don de rein à partir d'un donneur vivant ou d'un donneur en état de mort encéphalique (EME). L'immunisation des receveurs est une vraie problématique de la greffe car elle est responsable de difficultés particulières de choix d'un donneur et surtout expose au risque de rejet de greffon. Nous allons présenter deux observations de greffe rénale entre époux, ou les deux receveurs avaient des taux faibles d'anticorps dirigés contre des antigènes HLA du donneur mais dont l'issue en post-greffe immédiat était différente selon le sexe du receveur. En effet l'immunisation anti-HLA des femmes suite aux grossesses est un vrai obstacle à leur greffe par le rein de leur époux. Malgré la faible compatibilité HLA qui caractérise la transplantation rénale entre les époux, car le donneur est ici non apparenté, cette transplantation offre une bonne alternative aux greffes de reins à partir de donneurs en EME, qui font cruellement défaut au Maroc.

Non-cryopreserved peripheral blood stem cells autologous transplantation in multiple myeloma: Bicentric study

OBJECTIVES

The objective of this study is to evaluate the toxicity of autologous transplantation of non-frozen peripheral blood stem cells in Moroccan patients with multiple myeloma.

MATERIAL AND METHODS

This was a bicentric retrospective study conducted in the Clinical Haematology Department of Mohammed V Military Teaching Hospital and at the Al Madina Clinic in Casablanca. The study period was from January 2015 to June 2019. All patients with multiple myeloma who had undergone an autologous peripheral stem cell transplant without freezing were included. Mobilisation was performed with lenograstim alone and the collected stem cells were stored for 24-48hours in a blood bank refrigerator at a temperature of 4°C. After standard conditioning with high-dose melphalan, the peripheral blood stem cells were reinjected 24 h following conditioning.

RESULTS

Over the study period, 55 patients received an autologous transplant using non-frozen peripheral blood stem cells. The median richness of the CD34 cells collected was 4.5×10⁶ CD34/kg (range: 2-12.2). The time required for neutrophil recovery was 12 days (range: 7-19). The time required for platelet recovery was 14 days (range: 9-32). The mortality rate within 100 days post-transplant was 3.6%. We did not observe any cases of graft failure.

CONCLUSION

Our study finds good feasibility and low toxicity of autologous peripheral stem cell transplantation without freezing in patients with multiple myeloma.

HLA typing and haematopoietic stem cell transplantation in the histocompatibility unit of the Ibn Sina University Hospital in Rabat (Morocco)

PURPOSE OF STUDY

This study focuses on the search for a suitable related HLA-matched donor of haematopoietic stem cells in the context of allogeneic transplantation in Morocco. The aim of this work is to establish whether the related donor can meet graft needs in Moroccan patients.

PATIENTS AND METHODS

429 families (429 recipients and 965 donors) benefited from HLA typing, using microlymphocytotoxicity, polymerase chain reaction-sequence specific primer and/or high-resolution polymerase chain reaction-specific sequence oligonucleotide.

RESULTS

The recipients and donors are mostly men over 18 years of age. In total, 86.8% of the recipients have between 1 and 3 donors who are 96% of the collaterals. Malignant haemopathies account for 54% of allograft indications. Benign haemopathies are more frequent than malignant in children, whereas the profile is reversed in adults. Fifty percent of recipients have an HLA identical donor in their siblings and 42% and HLA haplo identical donor. The HLA typing of the recipients and the donors reveals very large polymorphism of the population.

CONCLUSION

The related donor of haematopoietic stem cells represents an important source of grafts but will not be able to satisfy all the needs of Morocco. The creation of national unrelated voluntary donors will open up new possibilities for recipients who do not have a compatible donor within his relatives.

Reason and Resolution of High Negative Control Beads in Solid-Phase Immunoassay

OBJECTIVES

The Luminex technology is the most sensitive diagnostic method for HLA antibody detection and identification. However, the interpretation of immunoassays is commonly affected by the artifact, and non-specific background. Sera from some patients show high negative control bead (NC) value, which makes assessing and interpretation of HLA antibodies difficult. In this study, we evaluated the effect of Adsorb Out reagent, dithiothreitol (DTT), and Ethylenediaminetetraacetic acid (EDTA) on the NC median fluorescence intensity value by comparing treated versus untreated patient sera. In addition, we wanted to identify whether kidney disease and administered medication influenced high NC median fluorescence intensity values by comparing patient versus control results.

MATERIALS AND METHODS

HLA antibody screening was performed on 3500 serum samples. Sera were analyzed using the standard protocol for Luminex antibody screening. Sera with high NC values were preincubated with Adsorb Out, DTT, and EDTA. Screening of these sera was then performed.

RESULTS

We found that 4% of samples showed high NC values. Adsorb Out, DTT, and EDTA decreased the NC values at 723.5 (299.25-1443) versus 85 (34-218; P < .001), at 723.5 (299.25-1443) versus 184 (106-597; P < .001), and at 723.5 (299.25-1443) versus 455 (131-1177; P = .004). These succeeded in bringing back NC values to normal range in 69.2%, 43%, and 30% of treated sera, respectively. In addition, the differences of corticoids, immunosuppressive, and heparin drugs between patients and controls were statistically significant (P < .001, < .001, and = .043). However, presence of kidney disease was not significant between these groups.

CONCLUSIONS

All pretreatments had an important effect in decreasing negative control values, with Adsorb Out having highest efficiency. Serum-specific components could contribute to high negative control bead median fluorescence intensity values. Further studies are needed to determine the adequate pretreatment of patient sera.

[Cytotoxicity of natural anti-HLA antibodies in Moroccan patients awaiting for kidney transplantation]

The presence of anti-HLA antibodies in the serum of a patient result from an immune response produced during an immunizing event as transfusion, pregnancy or graft. These antibodies can be cytotoxic by activating the complement pathway via C1q and may cause organ rejection during the transplant. Some male patients awaiting kidney transplantation are seropositive for anti-HLA antibodies when they have no immunizing antecedent event. These antibodies are qualified as natural antibodies. Our work is to assess the cytotoxicity of natural anti-HLA antibodies in patients followed at the immunology laboratory of the blood transfusion service and hemovigilance (STSH) as part of the kidney transplant.

PATIENTS AND METHODS

We evaluated the cytotoxicity of HLA antibodies detected in male Moroccan patients without immunization history using C1qScreen One Lambda reagent for Luminex™.

RESULTS

Non-immunized men were positive for HLA antibodies screening in 25.4%. These antibodies are not cytotoxic.

CONCLUSION

Our study showed a positivity rate of natural HLA antibody low than the literature (25.4% against 63%). It appears that these natural antibodies are not cytotoxic and their involvement in renal transplant remains to be determined.

[Serological tests for celiac disease in Moroccan patients with type 1 diabetes]

La maladie cœliaque (MC) est l'une des maladies auto-immunes les plus fréquemment associées au diabète de type 1 (DT1). La prévalence de MC dans DT1 varie de 3 à 6%. La présentation clinique de MC dans DT1 est classé comme asymptomatiques dans environ la moitié des cas. L'objectif de notre étude est de déterminer la fréquence des auto-anticorps anti-transglutaminase tissulaire (AtTG) et anti-gliadines (AAG) chez les patients diabétiques de type 1 dans le but de recommander une éventuelle biopsie jéjunale et d'instaurer un régime sans gluten précocement avant l'installation des signes cliniques et des complications de la maladie cœliaque. Les sujets inclus dans cette étude sont des patients atteints de DT1 non traités pour la MC et qui ne présentent pas de signes en faveur de cette pathologie. La détection des AtTG de classe IgG et IgA et AAG classe IgG et IgA a été réalisée par technologie Luminex. Nous avons inclus 31 patients. Il s'agit de 16 hommes et 15 femmes. Les AAG de classe IgA étaient positifs chez 4(13%) patients et chez 7(22,5%) patients pour les IgG. Les AtTG de classe IgA étaient positifs chez 3(10%) patients et chez une patiente (3%) pour les IgG. Dans notre étude l'association du diabète type 1 et des marqueurs biologiques de la MC n'est pas rare d'où l'intérêt de son dépistage systématique chez des diabétiques de type 1. Le diagnostic de cette forme atypique et silencieuse de la MC est important compte tenu du risque de complications sérieuses à type de malabsorption et de cancers digestifs.

[Immunological monitoring in kidney transplantation: 13 years experience of a Moroccan histocompatibility laboratory]

PURPOSE OF STUDY

The quality of the immunological monitoring is crucial because it determines the success of the kidney transplantation. The scope of this work is to describe the experience of the department of immunological unity of the Ibn Sina university hospital in Rabat regarding the immunological monitoring of patients transplanted between 2001 and 2014.

PATIENTS AND METHODS

Patient samples were collected from nephrology services of different public and private hospitals of Morocco. The tests conducted in the context of immunological monitoring are ABO typing, HLA-A, B, DR, DQ typing, anti-HLA antibodies detection and identification and cross-match.

RESULTS

One hundred and fourteen benefited from a pre- and post-transplant immunological monitoring in our laboratory. The percentage of recipients having between 2 and 5 stored sera is 60.5 before transplantation and 56.1 after transplantation. Immunized patients account for 22.8% before the transplant and 17.6% after transplantation. Ninety-seven patients still have a functional graft, while 4 of them had DSA of low intensity before transplantation. Five immunological rejections were reported while the cross-match were negative and no DSA was identified before transplantation. Patient survival and graft at 1 year was 98.2% and 92.7% respectively.

CONCLUSION

Conducting regular immunological monitoring is sometimes difficult in our context, however, the results are satisfactory in terms of graft and patients survival.

[The HLA system in the Moroccan population: General review]

The Moroccan population is an interesting study model of Human Leukocyte Antigen (HLA) polymorphism given its ethnic and genetic diversity. Through an analysis of the literature, this work proposes to establish a balance of knowledge for this population in the field of histocompatibility: HLA diversity, anthropology, transplantation and HLA associations and diseases. This analysis shows that the HLA system has not been fully explored within the Moroccan population. However, the results obtained allowed us to initiate a database reflecting the specific healthy Moroccan population HLA polymorphism to identify immigration flows and relationships with different people of the world and to reveal the association of certain HLA alleles with frequent pathologies. We also propose to analyze the reasons hindering the development of this activity in Morocco and we will try to identify some perspectives.

Moroccan study of HLA (-A, -B, -C, -DR, -DQ) polymorphism in 647 unrelated controls: Updating data

The scope of this study is to investigate the HLA (Human Leukocyte Antigen) distribution and polymorphism in a large sample of healthy Moroccans in order to extend and update the available data. 647 unrelated Moroccan controls originating from diverse regions of the country were typed using microlymphocytotoxicity for HLA-A and -B, sequence-specific-primer amplification for -C, -DR, and -DQ and Luminex HD for specific -DR. The most frequent allele groups detected were HLA-A2 (19.2%), -B44 (12.4%), -C*07 (24.4%), -DRB1*03 (16.9%), -DRB1*04 (18.4%), -DQB1*02 (28.7%) and -DQB1*03 (27.8%). The most predominant specific alleles found for DRB1 were: *03:01, *04:02, *04:05, *07:01, *11:01, *13:02 and *15:01. Rare allelic variants were detected, for the first time in Moroccan population, at the DRB1*03 (*03:52, *03:54, *03:56), DRB1*07 (*07:07, *07:11, *07:16) and DRB1*11 (*11:70) locus. The most frequent haplotypes were: A2-B44, A30-B18, A2-C*16, A30-C*06, B14-C*08, B58-C*07, B45-C*06, DRB1*03-DQB1*02, DRB1*04-DQB1*03, DRB1*07-DQB1*02 and DRB1*15-DQB1*06. Comparison of genetic distances and haplotypes with other populations shows that the Moroccans are genetically closer to North Africans and Europeans than to sub-Saharan Africans. Our results reflect the high degree of HLA polymorphism in the Moroccan population and provide a useful baseline of healthy Moroccan controls for disease association and anthropological studies.

[Management by objectives: an experience by transfusion and immunology service in Rabat]

The management by objectives method has become highly used in health management. In this context, the blood transfusion and haemovigilance service has been chosen for a pilot study by the Head Department of the Ibn Sina Hospital in Rabat. This study was conducted from 2009 to 2011, in four steps. The first one consisted in preparing human resources (information and training), identifying the strengths and weaknesses of the service and the identification and classification of the service's users. The second step was the elaboration of the terms of the contract, which helped to determine two main strategic objectives: to strengthen the activities of the service and move towards the "status of reference." Each strategic objective had been declined in operational objectives, then in actions and the means required for the implementation of each action. The third step was the implementation of each action (service, head department) so as to comply with the terms of the contract as well as to meet the deadlines. Based on assessment committees, the last step consisted in the evaluation process. This evaluation was performed using monitoring indicators and showed that management by objectives enabled the Service to reach the "clinical governance level", to optimize its human and financial resources and to reach the level of "national laboratory of reference in histocompatibility". The scope of this paper is to describe the four steps of this pilot study and to explain the usefulness of the management by objectives method in health management.

Distribution of HLA class I and II genes in ankylosing spondylitis patients from Morocco

OBJECTIVES

In Morocco, the patients affected by ankylosing spondylitis (AS) presents a high frequency of coxitis. Our study reports, for the first time, the polymorphism of Human Leukocyte Antigen (HLA) class I and class II molecules in the Moroccan patients.

METHODS

Forty-six patients diagnosed with an AS and coxitis were compared to a group of 183 healthy controls matched by age, sex and ethnic origin. The HLA typing was performed using microlymphocytotoxicity for the class I (-A, -B) and PCR-SSP for the class II (-DR, -DQ).

RESULTS

We found a significant increase of the HLA-B27 antigen frequency (P<0.0001, RR=20.9) in AS patients (29.3%) compared to the controls (3.2%) and a significant decrease in the frequency of HLA-B12 and HLA-B18 antigens. Examination of HLA class II distribution shows a significant increase of the HLA-DRB1*11 allele frequency in patients (P<0.0001). Concerning HLA-DQB1* alleles, no significant difference between patients and controls was appreciable.

CONCLUSIONS

The HLA-B27 antigen is involved in the predisposition to the AS with coxitis in the Moroccan population. However, the low frequency observed in our population suggests the existence of other genetic and/or environmental factors. Other HLA genes seem to confer a predisposing effect (DRB*11) or a protective effect (B12 and B18) against the disease.

[Traceability of labile blood products in Morocco: experience of the Ibn-Sina hospital of Rabat between 1999 and 2010]

PURPOSE OF STUDY

The blood transfusion and haemovigilance service of the Ibn-Sina hospital in Rabat (Morocco) was created 1997. This unit manages the pretransfusional tests, distribution of blood products, traceability and haemovigilance. The objective of this study was to analyze, over a period of 12years, the traceability of blood products delivered in our hospital and the measures used to improve feedback information.

PATIENTS AND METHODS

This is a retrospective study conducted between 1999 and 2010. Traceability rate was calculated from the feedback of traceability forms supplied with blood products (number of blood products noted on traceability forms on the total number of delivered product). To improve traceability rate, several actions were undertaken: one-time training, awareness campaigns and call phones asking for feedback information.

RESULTS

Between 1999 and 2010, the service has delivered 173,858 blood products. The average rate of traceability during this period was 13.4 %. Traceability rate varies widely over time (5.2 % in 1999, 15.5 % in 2010) and shows a maximum value of 27.2 % in 2005. Feedback information is lower in emergency departments than in medical and surgical services.

CONCLUSION

Feedback information about traceability in Ibn-Sina hospital remains very poor despite the measures used. Other actions, such as continuous education courses, low enforcement and informatisation should be considered.

Profile and course of early rheumatoid arthritis in Morocco: a two-year follow-up study

Background

This study aimed to establish the profile and the evolution of an early Rheumatoid arthritis (RA) cohort in the Moroccan population and also to search possible predictor factors of structural progression.

Methods

Patients with early RA (< 12 months) were enrolled in a 2-year follow-up study. Clinical, biological, immunogenetic, and radiographical data were analyzed at study entry and at 24 months. Presence of radiographic progression was retained when the total score was superior to the smallest detectable difference (SDD) calculated to be 5.4 according the Sharp/van der Heijde (SVDH) method.

Results

Fifty one patients (88.8% women, mean age of 46.9 [ 24-72 ] ± 10.8 years, mean disease duration of 24 [ 6-48 ] ± 13.9 weeks) were enrolled in this study. 68.6% were illiterate and 19.6% reported at least one comorbid condition. The mean delay in referral for specialist care was 140 [ 7-420 ] ± 43 days.

Thirteen patients (62.5%) were IgM or IgA RF positive. HLA-DRB1*01 and DRB1*04 alleles were present respectively in 11.8% and 45.1% of patients.

At baseline, 35.3% patients were taking corticosteroids and 7.8% were under conventional DMARDs.

At 24 months, 77.2% received a median dose of 5 mg/day of prednisone. Methotrexate (MTX) was the most frequently prescribed DMARD, being taken by 65.2% of patients. 13.6% of patients had stopped their DMARD because of socioeconomic difficulties.

Comparison of clinical and biologic parameters between baseline and 24 months thereafter revealed a significant global improvement of the disease status including morning stiffness, pain score, swollen joint count, DAS 28 and HAQ scores, ESR and CRP.

Sixteen patients (34.8%) were in remission at 2 years versus no patients at baseline; P < 0.001.

Forteen patients (27.5%) had at least one erosion at baseline. Radiographic progression occurred in 33.3% of patients and was associated in univariate analysis to swollen joint count (p = 0.03), total SVDH score (P = 0.04) and joint space narrowing score (P = 0.03). No independent factors of radiographic progression were shown by logistic regression.

Conclusions

These study reports, provided for the first time in Morocco, a developing African country, a large amount of information concerning the profile and the course of early RA.

Patients who were receiving, for most of them, Methotrexate in monotherapy and low doses of corticosteroids, showed an improvement of all clinic and biologic disease parameters. Moreover, DAS remission was obtained in one third of patients and two thirds of the cohort had no radiographic progression at 2 years. No predictor factors of radiographic progression were found out.

These results should be confirmed or not by a large unbiased RA cohort which will give more relevant information about early RA characteristics and its course and will constitute a major keystone of its management.

[Rejection of kidney graft: mechanism and prevention]

Rejection occurs after the introduction of a genetically different graft, in a recipient. Nowadays, it is still a major obstacle in renal transplantation and reflects a normal protective immune response of a recipient against a foreign antigen. Involving many mechanisms of the innate and adaptive immunity, this reaction results in renal parenchymal lesions witch may progress to graft destruction and loss of its function. Several ways are currently used to reduce the action of the immune system and consequently reduce the risk of rejection. After a presentation of the main actors and the sequence of events leading to rejection, we will describe the strategy used by antirejection teams' transplantation. We will successively consider the prevention (pre-transplant immunological assessment, preventive immunosuppressive therapy), the monitoring (search for antibodies, biopsies) and the treatment.

[The latest TH17 lymphocyte in the family of T CD4+ lymphocytes]

In recent years the T CD4+ lymphocyte family has grown. In the initial two components TH1 and TH2 lymphocytes were added the TH17 lymphocyte and T cell regulator (Treg). Under the influence of transforming growth factor β, interleukin 6 (IL6), IL21 and IL23, the naive lymphocyte T CD4+ differentiates in TH17. Currently, the TH17 is recognized as the leading actor of local inflammation through the pro-inflammatory cytokines (interleukins 17, 21, 22) that secretes and the expansion and recruitment of neutrophils that leads. Therefore, it is involved in chronic inflammatory processes, autoimmune diseases (rheumatoid arthritis, systemic lupus erythematosus), allergy and rejection of allogeneic transplants. TH17 lymphocyte opens up new therapeutic prospects for these pathologies.

[Toll-like receptors]

The toll-like receptors are innate immunity receptors which recognise particular exogenous structures in the microorganisms pathogen associated molecular pattern (PAMP) and endogenous structures damage-associated molecular patterns (DAMP). Eleven TLR have been identified among human beings. These are danger receptors located in the cells of the immune system but also in other cells. Their primary function is the recognition of pathogens and the activation of the cell that holds them. It follows from it an action on the cells environment, inflammation cells and an activation of the adaptive immunity. The knowledge of the intracellular signalisation ways of the TLR has allowed us to understand the physiopathology of certain diseases. Thus, several works use the agonists of TLR to stimulate them: vaccines against infectious diseases, allergies and cancers. The antagonists are used to block the TLR in autoimmune and chronic inflammatory diseases. It is clear that the border between innate and adaptive immunity fades and that these two components of the immune response are closely related, thus opening up new prospects diagnostic and therapeutic procedures.

HLA-A, -B, -DR and -DQ allele and haplotype frequencies in the Moroccan population: a general population study

PURPOSE OF STUDY

The aim of this general population study is to extend our knowledge about the HLA-A, -B, -DR and -DQ genes distribution and their diversity among the Moroccan population.

PATIENTS AND METHODS

One hundred and ten unrelated healthy Moroccans from diverse regions of the country were included in the study. HLA typing was done either by serological (standard complement dependent microlymphocytotoxicity) and/or molecular (sequence-specific primer amplification) techniques.

RESULTS

The most frequent alleles observed were: HLA-A2 (19.1%), -A1 (10%), -A3 (10%), -B44 (9.6%), -DR3 (17.1%), -DR4 (15.3%), -DQ2 (30.6%), -DQ6 (26.4%) and -DQ3 (25%). No predominant haplotype was observed for HLA A-B while high frequency was observed for some HLA DR-DQ associations (DR3-DQ2, DR15-DQ6, DR7-DQ2, DR4-DQ3, DR13-DQ6). Comparison with neighbouring populations, on the basis of alleles, haplotypes and genetic distances, showed that Moroccan population is close to the Algerians, the Tunisians, the Spaniards and the French. The haplotype frequencies revealed also relationships with Italians, Sardinians, Basques, Portuguese and Moroccan Jews populations.

CONCLUSION

Our results confirm and extend the current knowledge about the Moroccan genetic pattern and reflect all the ethnic diversity of the country. This study will be helpful in the future for clinical analysis like transplantation and HLA-associated diseases in Moroccan population.