RESUMO
We report five individuals with loss-of-function of the X-linked AMMECR1: a girl with a balanced X-autosome translocation and inactivation of the normal X-chromosome; two boys with maternally inherited and de novo nonsense variants; and two half-brothers with maternally inherited microdeletion variants. They present with short stature, cardiac and skeletal abnormalities, and hearing loss. Variants of unknown significance in AMMECR1 in four male patients from two families with partially overlapping phenotypes were previously reported. AMMECR1 is coexpressed with genes implicated in cell cycle regulation, five of which were previously associated with growth and bone alterations. Our knockdown of the zebrafish orthologous gene resulted in phenotypes reminiscent of patients' features. The increased transcript and encoded protein levels of AMMECR1L, an AMMECR1 paralog, in the t(X;9) patient's cells indicate a possible partial compensatory mechanism. AMMECR1 and AMMECR1L proteins dimerize and localize to the nucleus as suggested by their nucleic acid-binding RAGNYA folds. Our results suggest that AMMECR1 is potentially involved in cell cycle control and linked to a new syndrome with growth, bone, heart, and kidney alterations with or without elliptocytosis.
Assuntos
Osso e Ossos/fisiologia , Coração/fisiologia , Proteínas/genética , Animais , Western Blotting , Osso e Ossos/metabolismo , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular , Exoma/genética , Feminino , Células HeLa , Humanos , Masculino , Sequenciamento Completo do Genoma , Peixe-ZebraRESUMO
BACKGROUND: The treatment of Plasmodium vivax infections requires the use of primaquine, which can lead to severe haemolysis in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. However, most of the Latin American countries, which are still endemic for vivax malaria, lack information on the distribution of G6PD deficiency (G6PDd). No survey has been performed so far in French Guiana. Herein, 80 individuals of the French Guianan Noir Marron population were scrutinized for red cell surface antigens of six blood group systems (ABO, Rh, Kell, Kidd, Duffy and MNS) and G6PD genetic polymorphisms. First, the sub-Saharan origin of the red cell phenotypes was assessed in relation with the literature. Then, given that the main sub-Saharan G6PDd variants are expected to be encountered, only the G6PD sequences of exons 4, 5, 6 and 9 were screened. This work aims at appraising the G6PD gene variation in this population, and thus, contributing to the G6PD piecemeal information in Latin America. RESULTS: Ninety-seven percent (97 %) of the red cells are Fy(a- b-), either D+ C- E- c+ e+ or D+ C+ E- c+ e+ and 44 % exhibited the Fya-/Jkb-/S- combined phenotype. Noteworthy is the detection of the G6PD(Val68Met) variant characterized by c.202G > A transition, G6PD(Asn126Asp) variant characterized by c.376A>G transition and G6PD(Asp181Val) variant characterized by c.542A>T transversion of the G6PD gene in 22.5 % of the sample, characteristic of the A(-(202)), A and Santamaria G6PDd variants, respectively. CONCLUSIONS: French Guianan Noir Marron population represents a pool of Rh-D antigen positive, Duffy-negative and G6PD-deficient erythrocytes, the latter accounting for one in every eight persons. The present study provides the first community-based estimation of the frequency of G6PDd polymorphisms in French Guiana. These results contribute to the G6PD genetic background information puzzle in Latin America.