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Congenital anomaly registries have two main surveillance aims: firstly to define baseline epidemiology of important congenital anomalies to facilitate programme, policy and resource planning, and secondly to identify clusters of cases and any other epidemiological changes that could give early warning of environmental or infectious hazards. However, setting up a sustainable registry and surveillance system is resource-intensive requiring national infrastructure for recording all cases and diagnostic facilities to identify those malformations that that are not externally visible. Consequently, not all countries have yet established robust surveillance systems. For these countries, methods are needed to generate estimates of prevalence of these disorders which can act as a starting point for assessing disease burden and service implications. Here, we describe how registry data from high-income settings can be used for generating reference rates that can be used as provisional estimates for countries with little or no observational data on non-syndromic congenital malformations.
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Background: We conducted a meta-analysis of articles published between January 2000 and July 2016 with the aim of defining the proportion of rubella seronegative women of childbearing age (WCBA), providing the best information available on the seroprevalence of rubella in this population. We selected articles published in the time period between 2000 and 2016. The pooled prevalence of rubella seronegative women was calculated by a fixed effect model and a random effect model, according to the heterogeneity among studies. Studies were sub-grouped by population type (pregnant women and WCBA with no mention of ongoing pregnancy) and by geographic area [World Health Organization (WHO) region]. Sensitivity analysis was performed to assess the stability of results. We found important differences in rubella seronegativity prevalence estimates by WHO Region. About 88% of the studies conducted on pregnant women reported a seronegativity rate >5%. The pooled rubella seronegativity prevalence was 9.3%. When considering population groups, we obtained a seronegativity pooled estimate of 9.4% for pregnant women and of 9.5% for WCBA with no mention of ongoing pregnancy. This meta-analysis shows that the proportion of WCBA who are susceptible to rubella is still high. The figures are worrisome, taking into account that the WHO set at 5% the rubella susceptibility threshold for WCBA.
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Complicações Infecciosas na Gravidez/epidemiologia , Rubéola (Sarampo Alemão)/epidemiologia , Adolescente , Adulto , Feminino , Saúde Global/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Soroepidemiológicos , Adulto JovemRESUMO
OBJECTIVE: We used data from a national study of pregnant women with HIV to evaluate the prevalence of congenital abnormalities in newborns from women with HIV infection. DESIGN: Observational study. SETTING: University and hospital clinics. POPULATION: Pregnant women with HIV exposed to antiretroviral treatment at any time during pregnancy. METHODS: The total prevalence of birth defects was assessed on live births, stillbirths, and elective terminations for fetal anomaly. The associations between potentially predictive variables and the occurrence of birth defects were expressed as odds ratios (ORs) with 95% confidence intervals (95% CIs) for exposed versus unexposed cases, calculated in univariate and multivariate logistic regression analyses. MAIN OUTCOME MEASURES: Birth defects, defined according to the Antiretroviral Pregnancy Registry criteria. RESULTS: A total of 1257 pregnancies with exposure at any time to antiretroviral therapy were evaluated. Forty-two cases with major defects were observed. The total prevalence was 3.2% (95% CI 1.9-4.5) for exposure to any antiretroviral drug during the first trimester (23 cases with defects) and 3.4% (95% CI 1.9-4.9) for no antiretroviral exposure during the first trimester (19 cases). No associations were found between major birth defects and first-trimester exposure to any antiretroviral treatment (OR 0.94, 95% CI 0.51-1.75), main drug classes (nucleoside reverse transcriptase inhibitors, OR 0.95, 95% CI 0.51-1.76; non-nucleoside reverse transcriptase inhibitors, OR 1.20, 95% CI 0.56-2.55; protease inhibitors, OR 0.92, 95% CI 0.43-1.95), and individual drugs, including efavirenz (prevalence for efavirenz, 2.5%). CONCLUSIONS: This study adds further support to the assumption that first-trimester exposure to antiretroviral treatment does not increase the risk of congenital abnormalities.
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Anormalidades Induzidas por Medicamentos/epidemiologia , Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Inibidores da Transcriptase Reversa/efeitos adversos , Anormalidades Induzidas por Medicamentos/etiologia , Adolescente , Adulto , Peso ao Nascer , Estudos de Coortes , Coinfecção/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/epidemiologia , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Itália/epidemiologia , Masculino , Exposição Materna , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Primeiro Trimestre da Gravidez , Prevalência , Adulto JovemRESUMO
BACKGROUND AND AIMS: The relevance of folate, other B-vitamins and homocysteine (Hcy) for the occurrence or prevention of several diseases has induced growing interest. Unfortunately, little evidence is available regarding B-vitamin concentrations in Italy. This study evaluated in a region of middle-southern Italy, folate, vitamin B12 and Hcy concentrations and the prevalence of their ideal blood levels. The main determinants of B-vitamins and Hcy were also considered. METHODS AND RESULTS: Male and female blood donors (n=240), aged 18-66 years and living in Molise region (Italy), were enrolled in the study. They completed a brief questionnaire concerning fruit and vegetables intake, physical activity and smoking; serum and red blood cell (RBC) folate and serum vitamin B12 were measured by an immunoassay on an automated analyzer. Total Hcy was measured by high performance liquid chromatography (HPLC). Geometric means of serum folate, RBC folate and serum vitamin B12 were 10.8nmoll(-1), 426.0nmoll(-1) and 245.0pmoll(-1), respectively. Only 22.5%, 24.2% and 16.3% of blood donors showed an adequate level of serum folate, RBC folate or serum vitamin B12 respectively. When a cut-off of RBC folate ≥906nmoll(-1) was used no women of childbearing age had adequate levels. A geometric mean of 14.0µmoll(-1) was found for total Hcy, with an ideal concentration in 12.1% of subjects. Folate concentration was higher in women and non-smokers and in subjects with higher consumption of fruit and vegetable. CONCLUSION: This study shows a low-moderate B-vitamins status in middle-southern Italy, associated with an inadequate fruit and vegetable consumption. A public health strategy should be undertaken to encourage a B-vitamin-rich diet with the addition of vitamin supplements or vitamin fortified foods in population subgroups with special needs.
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Doadores de Sangue , Comportamento Alimentar , Ácido Fólico/sangue , Homocisteína/sangue , Vitamina B 12/sangue , Adolescente , Adulto , Idoso , Cromatografia Líquida de Alta Pressão , Feminino , Frutas , Humanos , Itália , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Manejo de Espécimes , Inquéritos e Questionários , Verduras , Adulto JovemAssuntos
Recém-Nascido de Baixo Peso , Exposição Materna/efeitos adversos , Primeiro Trimestre da Gravidez , Lesões por Radiação/etiologia , Glândula Tireoide/efeitos da radiação , Raios X/efeitos adversos , Adulto , Peso ao Nascer , Relação Dose-Resposta à Radiação , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Lesões por Radiação/epidemiologiaRESUMO
This paper concerns the first phase of a study about the perception of social and health needs of people with rare diseases. The study was performed by the National Center for Rare Diseases at the Italian National Institute of Health (Istituto Superiore di Sanità - ISS). The project wants to be an example of collaboration between the research and the association worlds. Responsible of Associations of Patients and their relatives were asked their opinion about the accessibility and quality of important features of health and social services (accessibility and quality of diagnostic, pharmacological, psychological and rehabilitative interventions, social support, school and vocational training, information that was given to relatives). An ad hoc questionnaire was developed through focus groups. The questionnaire was completed by 108 associations (26,5% of the associations thar are recorded in the ISS database). Average scores showed satisfaction only for some variables and a negative gradient north-south was observed. The most frequent complaints were about information, quality of school and job training services and availability of psychological support. The study showed an high level of dissatisfaction with availability, quality and integration health and social services.
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Pesquisa Biomédica , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Doenças Raras , Serviço Social/estatística & dados numéricos , Instituições Filantrópicas de Saúde , Academias e Institutos , Comportamento Cooperativo , Acessibilidade aos Serviços de Saúde/normas , Humanos , Itália , Organizações sem Fins Lucrativos , Satisfação do Paciente/estatística & dados numéricos , Projetos Piloto , Serviço Social/normas , Sociedades , Inquéritos e QuestionáriosRESUMO
Most international trials support the recommendation that all women planning or at risk of pregnancy take a daily multivitamin supplement containing folic acid, beginning one month before conception and continuing through the first trimester for primary prevention of neural tube defects and other congenital malformations. Recently an intervention project started also in Italy, in order to support and maintain the periconceptional supplementation and to evaluate the efficacy of a national preventive campaign on parents' behaviour.
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Anormalidades Congênitas/prevenção & controle , Deficiência de Ácido Fólico/prevenção & controle , Ácido Fólico/administração & dosagem , Gravidez , Adulto , Ensaios Clínicos como Assunto , Feminino , Humanos , Recém-Nascido , Itália , Defeitos do Tubo Neural/prevenção & controle , Pais , Primeiro Trimestre da Gravidez , Prevenção Primária , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Fatores de TempoAssuntos
Alelos , Etnicidade/genética , Variação Genética/genética , Oxirredutases/genética , Frequência do Gene/genética , Genética Populacional/métodos , Genética Populacional/estatística & dados numéricos , Humanos , Recém-Nascido , Metilenotetra-Hidrofolato Desidrogenase (NAD+) , Modelos Genéticos , Triagem Neonatal/métodosRESUMO
In the last decade a high frequency of other congenital anomalies has been reported in infants with congenital hypothyroidism (CH) detected by neonatal screening. In the present study the occurrence of additional congenital malformations (CM) in the population of CH infants detected in Italy between 1991 and 1998 (n = 1420) was investigated. In Italy all of the centers in charge of screening, treatment, and follow-up of CH adhere to the Italian National Registry of infants with CH. In this study a high prevalence of additional CM (8.4%), more than 4-fold higher than that reported in the Italian population (1-2%), was found in the population of CH infants. Cardiac anomalies represented the most frequent malformations associated with CH, with a prevalence of 5.5%. However, a significant association between CH and anomalies of nervous system, eyes, and multiple CM was also observed. In conclusion, the significantly higher frequency of extrathyroidal congenital malformations reported in the CH infants than in the general population represents a further argument supporting the role of a genetic component in the etiology of CH. Investigations of the molecular mechanisms underlying developmental events of formation of thyroid and other organs represent critical steps in the knowledge of CH etiology.
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Anormalidades Congênitas/epidemiologia , Hipotireoidismo Congênito , Hipotireoidismo/complicações , Anormalidades Múltiplas/epidemiologia , Anormalidades do Olho/complicações , Anormalidades do Olho/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Itália , Masculino , Triagem Neonatal/normas , Malformações do Sistema Nervoso/complicações , Malformações do Sistema Nervoso/epidemiologia , Prevalência , Sistema de RegistrosRESUMO
We report two patients with clinical and radiological findings of achondroplasia, who had the most common FGFR3 mutation occurring in thanatophoric dysplasia type I and hypochondroplasia, respectively. Thanatophoric dysplasia is usually a lethal condition, but the patient carrying this mutation is alive and presents a medical history similar to that of patients with achondroplasia. The events leading to such a discrepancy between genotype and phenotype are unclear. These rare cases may influence an appropriate medical and genetic counseling.
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Acondroplasia/genética , Proteínas Tirosina Quinases , Receptores de Fatores de Crescimento de Fibroblastos/genética , Displasia Tanatofórica/genética , Acondroplasia/patologia , Sequência de Bases , DNA/química , DNA/genética , Análise Mutacional de DNA , Humanos , Recém-Nascido , Masculino , Mutação de Sentido Incorreto , Fenótipo , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos , Displasia Tanatofórica/patologiaRESUMO
BACKGROUND: A specific phenotype of methimazole (MMI) induced malformations has recently been postulated. MMI embryopathy is characterized by minor dysmorphic features, choanal atresia and/or esophageal atresia, growth retardation, and developmental delay. METHODS: We prospectively studied the outcome of pregnancy in 241 women counseled by 10 Teratology Information Services (TIS) of the European Network of Teratology Information Services (ENTIS) because of MMI exposure, and compared them with those of 1,089 pregnant women referred to TIS because of exposure to nonteratogenic drugs (control group). Information was obtained by mail or telephone interview. RESULTS: There was no increase in the general rate of major anomalies or of spontaneous or induced abortions in the MMI-exposed group in comparison with the control group. Two newborns were affected with one of the major malformations that are part of the postulated embryopathy. CONCLUSIONS: The results of this study indicate that choanal as well as esophageal atresia may have a higher incidence than expected in fetuses exposed to MMI between 3 and 7 gestational weeks. Until further data are available, thyrotoxicosis should be treated with propylthiouracil, as it is apparently safer for use during the fertile period.
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Anormalidades Induzidas por Medicamentos/diagnóstico , Metimazol/efeitos adversos , Teratogênicos , Aborto Espontâneo , Adulto , Fatores Etários , Peso Corporal , Estudos de Coortes , Deficiências do Desenvolvimento/induzido quimicamente , Atresia Esofágica/induzido quimicamente , Europa (Continente) , Feminino , Humanos , Recém-Nascido , Serviços de Informação , Masculino , Fenótipo , Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Fatores de TempoRESUMO
OBJECTIVE: Because there are no studies available on the safety of venlafaxine during pregnancy, the authors' goal in this study was to determine whether venlafaxine increases the risk for major malformations. METHOD: Data on 150 women exposed to venlafaxine during pregnancy in seven pregnancy counseling centers were compared with data from studies of pregnant women who 1) received selective serotonin reuptake inhibitor antidepressants (SSRIs) (N=150) and 2) who received nonteratogenic drugs (N=150). RESULTS: Among the 150 women who were exposed to venlafaxine during pregnancy, 125 had live births, 18 had spontaneous abortions, and seven had therapeutic abortions; two of the babies had major malformations. There were no significant differences between these women and the two comparison groups on any of the measures analyzed. CONCLUSIONS: These results suggest that the use of venlafaxine during pregnancy does not increase the rates of major malformations above the baseline rate of 1%-3%.
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Anormalidades Induzidas por Medicamentos/epidemiologia , Cicloexanóis/efeitos adversos , Transtorno Depressivo/tratamento farmacológico , Troca Materno-Fetal , Complicações na Gravidez/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Anormalidades Induzidas por Medicamentos/etiologia , Aborto Espontâneo/induzido quimicamente , Aborto Espontâneo/epidemiologia , Aborto Terapêutico/estatística & dados numéricos , Peso ao Nascer/efeitos dos fármacos , Cicloexanóis/uso terapêutico , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Exposição Materna/efeitos adversos , Gravidez , Resultado da Gravidez/epidemiologia , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Fatores de Risco , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Fumar/efeitos adversos , Cloridrato de VenlafaxinaRESUMO
In humans, unpaired organs are placed in a highly ordered pattern along the left-right axis. As indicated by animal studies, a cascade of signaling molecules establish left-right asymmetry in the developing embryo. Some of the same genes are involved also in limb patterning. To provide a better insight into the connection between these processes in humans, we analysed the symmetry of limb deficiencies among infants with multiple congenital anomalies. The study was based on data collected by the International Clearinghouse for Birth Defects Monitoring Systems (ICBDMS). Registries of the ICBDMS provided information on infants who, in addition to a limb deficiency, also had at least one major congenital anomaly in other organ systems. We reviewed 815 such cases of which 149 cases (18.3 %) were syndromic and 666 (81.7 %) were nonsyndromic. The comparisons were made within the associated limb deficiencies, considering the information on symmetry, using a comparison group with malformations associated not involved in the index association. Among the non-syndromic cases, the left-right distribution of limb deficiencies did not differ appreciably between limb deficiency subtypes (e.g., preaxial, transverse, longitudinal). The left-right distribution of limb anomalies did not differ among most types of non-limb anomalies, though a predominance of left-sided limb deficiencies was observed in the presence of severe genital defects - odds ratio [OR], 2.6; 95 % CI, 1.1-6.4). Limb deficiencies (LDs) were more often unilateral than bilateral when accompanied by gastroschisis (OR, 0.1) or axial skeletal defects (OR, 0.5). On the contrary, LDs were more often bilateral than unilateral when associated with cleft lip with or without cleft palate (OR, 3.9) or micrognathia (OR, 2.6). Specifically, we found an association between bilateral preaxial deficiencies and cleft lip, bilateral amelia with gastroschisis and urinary tract anomalies, and bilateral transverse deficiencies and gastroschisis and axial skeleton defects. Of 149 syndromic cases, 62 (41.6 %) were diagnosed as trisomy 18. Out of the 30 cases of trisomy 18 with known laterality, 20 cases were bilateral. In the remainder the right and left sides were equally affected. Also, in most cases (74.4 %) only the upper limbs were involved. In conclusion the left-right distribution of limb deficiencies among some non-limb anomalies may suggest a relationship between the development of the limb and the left-right axis of the embryo.
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Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/genética , Padronização Corporal/genética , Deformidades Congênitas dos Membros/epidemiologia , Deformidades Congênitas dos Membros/genética , Sistema de Registros , Anormalidades Múltiplas/classificação , Europa (Continente)/epidemiologia , Lateralidade Funcional , Humanos , Lactente , Recém-Nascido , Deformidades Congênitas dos Membros/classificação , Síndrome , TrissomiaRESUMO
Probiotics enriched in lactobacilli have been proposed as an effective and alternative tool to antibiotics for the treatment of bacterial vaginosis. The protective role of H(2)O(2)-producing lactobacilli has been strongly emphasized, but no clear-cut correlation appears to link the metabolic characteristics of administered lactobacilli with the clinical impact of probiotic therapy. On account of our review of basic mechanisms involved in bacterial vaginosis, we suggest that lactobacilli with an elevated arginine deiminase activity could have a greater therapeutic potential than strains producing only H(2)O(2). Preliminary results from our laboratory have demonstrated that treatment with probiotics containing arginine deiminase-positive lactobacilli improves clinical symptoms and is paralleled by a significant decline of polyamine levels in vaginal microenvironment. This is of outstanding interest due to the central role of polyamines in the pathogenesis of bacterial vaginosis. We should critically rethink, against this perspective, the use of probiotics for the treatment of affected women.
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Probióticos/uso terapêutico , Vaginose Bacteriana/terapia , Antibacterianos/uso terapêutico , Poliaminas Biogênicas/metabolismo , Feminino , Humanos , Hidrolases/metabolismo , Lactobacillus/enzimologia , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/imunologia , Vaginose Bacteriana/microbiologiaRESUMO
This study was undertaken to find a strict, unbiased epidemiological delineation of the VATER non-random association of congenital malformations and, based on registry information, to identify a group of probable VATER association infants suitable for etiological analyses. Information on 5,260 infants with multiple malformations was collected from four large registers of congenital malformations. Data were analyzed using a statistical method in which various putative confounders were controlled for. Our results indicate the existence of a distinct group of malformations corresponding to the VATER association: esophageal atresia, anal atresia, upper preaxial limb reduction defects, and costo-vertebral malformations. A subdivision into an upper and a lower group of VATER association was indicated, with heart malformations associated with the upper group and kidney malformations associated with the lower group. Restricting the inclusion criteria for VATER association to the above mentioned core malformations, few infants seem to belong to the VATER association, thus limiting the possibilities of carrying out etiological analyses. A relatively large number of infants may belong to a family of related conditions among which VATER association is a subgroup. In the search for risk factors, a strict definition of the VATER association is needed in order to not dilute the study material with irrelevant cases. The present study provides such strict inclusion criteria.
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Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/etiologia , Anus Imperfurado , Interpretação Estatística de Dados , Feminino , França/epidemiologia , Cardiopatias Congênitas , Humanos , Recém-Nascido , Itália/epidemiologia , Rim/anormalidades , Masculino , Sistema de Registros , América do Sul/epidemiologia , Coluna Vertebral/anormalidades , Suécia/epidemiologia , Síndrome , Fístula TraqueoesofágicaRESUMO
PURPOSE: The study goal was to assess teratogenic effects of antiepileptic drugs (AEDs) through the use of a surveillance system (MADRE) of infants with malformations. METHODS: Information on all malformed infants (1990-1996) with maternal first-trimester drug exposure was collected by the International Clearinghouse for Birth Defects and Monitoring Systems (ICBDMS). Cases were defined as infants presenting with a specific malformation, and controls were defined as infants presenting with any other birth defect. Exposure was defined by the use of AEDs during the first trimester of pregnancy. The association of AEDs with malformations was then estimated by calculating the odds ratios with 95% confidence intervals and testing their homogeneity among registries. RESULTS: Among 8005 cases of malformations, 299 infants were exposed in utero to AEDs. Of those exposed to monotherapy, 65 were exposed to phenobarbital, 10 to methylphenobarbital, 80 to valproic acid, 46 to carbamazepine, 24 to phenytoin, and 16 to other AEDs. Associations were found for spina bifida with valproic acid. Infants exposed to phenobarbital and to methylphenobarbital showed an increased risk of oral clefts. Cardiac malformations were found to be associated with phenobarbital, methylphenobarbital, valproic acid, and carbamazepine. Hypospadias was associated with valproic acid. Porencephaly and other specified anomalies of brain, anomalies of face, coarctation of aorta, and limb reduction defects were found to be associated with valproic acid. CONCLUSIONS: Using the MADRE system, we confirmed known teratogenic effects of AEDs. We also found increased risks for malformations that had never been reported associated with AEDs or for which the association was suggested by case reports.
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Anormalidades Induzidas por Medicamentos/epidemiologia , Anticonvulsivantes/efeitos adversos , Bases de Dados Factuais/estatística & dados numéricos , Epilepsia/tratamento farmacológico , Anormalidades Induzidas por Medicamentos/etiologia , Anticonvulsivantes/uso terapêutico , Feminino , Saúde Global , Humanos , Gravidez , Vigilância de Produtos Comercializados/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Fatores de Risco , Organização Mundial da SaúdeAssuntos
Anormalidades Múltiplas/etiologia , Anemia de Fanconi/complicações , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , GravidezRESUMO
We report on a clinical-genetic study of 16 Wolf-Hirschhorn syndrome (WHS) patients. Hemizygosity of 4p16.3 was detected by conventional prometaphase chromosome analysis (11 patients) or by molecular probes on apparently normal chromosomes (4 patients). One patient had normal chromosomes without a detectable molecular deletion within the WHS "critical region." In each deleted patient, the deletion was demonstrated to be terminal by fluorescence in situ hybridization (FISH). The proximal breakpoint of the rearrangement was established by prometaphase chromosome analysis in cases with a visible deletion. It was within the 4p16.1 band in six patients, apparently coincident with the distal half of this band in five patients. The extent of each of the four submicroscopic deletions was established by FISH analyses with a set of overlapping cosmid clones spanning the 4p16.3 region. We found ample variations in both the size of the deletions and the position of the respective breakpoints. The precise definition of the cytogenetic defect permitted an analysis of the genotype-phenotype correlations in WHS, leading to the proposal of a set of minimal diagnostic criteria, which in turn may facilitate the selection of critical patients in the search for the gene(s) responsible for this disorder. We observed that genotype-phenotype correlations in WHS mostly depend on the size of the deletion, a deletion of <3.5 Mb resulting in a mild phenotype, in which malformations are absent. The absence of a detectable molecular deletion is still consistent with a WHS diagnosis. Based on these observations a "minimal" WHS phenotype was inferred, the clinical manifestations of which are restricted to the typical facial appearance, mild mental and growth retardation, and congenital hypotonia.