Kallmann syndrome (KS) consists of congenital, isolated, idiopathic hypogonadotropic hypogonadism (IHH) and anosmia. The gene responsible for the X-linked form of KS, KAL, encodes a protein, anosmin, that plays a key role in the migration of GnRH neurons and olfactory nerves to the hypothalamus. In addition to X-linked pedigrees, autosomal dominant and recessive kindreds with KS have been reported. The relative importance of these autosomal vs. X-linked genes in producing KS, and the frequency of KAL mutations, are currently unknown because these are rare disorders and large series are unusual.We examined 101 individuals with IHH (Ϯ anosmia) and their families to determine their modes of inheritance, incidence of mutations in the coding sequence of KAL, genotype-phenotype correlations, and [in a subset (n ϭ 38)] their neuroendocrine phenotype.Of the 101 patients, 59 had true KS (IHH ϩ anosmia/hyposmia); whereas, in the remaining 42, no anosmia was evident in the patients or their families. Of the 59 KS patients, 21 were familial, whereas 38 were sporadic cases. Mutations in the coding sequence of KAL were identified in only 3 of 21 familial cases (14%) and 4 of 38 (11%) of the sporadic cases. Of the X-linked cases confirmed by mutational analysis, only 1 of 3 pedigrees appeared X-linked by inspection whereas the other 2 contained only affected brothers. Female members of known KAL mutation families (n ϭ 3) exhibited no reproductive phenotype and were not anosmic, whereas families with anosmic women (n ϭ 3) were not found to carry mutations in KAL. Mutations were uniformly absent in nonanosmic IHH probands (n ϭ 42), as well as in families with both anosmic and nonanosmic members (n ϭ 2). Overall, 4 novel mutations were identified (C172R, R191ϫ, R457ϫ, and delC@L600).With respect to neuroendocrine phenotype, KS men with documented KAL mutations (n ϭ 8) had completely apulsatile LH secretion, whereas those with autosomal modes of inheritance demonstrated a more variable spectrum with evidence of enfeebled (but present) GnRH-induced LH pulses.Our conclusions are: 1) Confirmed mutations in the coding sequence of the KAL gene occur in the minority of KS cases, i.e. only 14% of familial and 11% of sporadic cases; 2) The majority of familial (and presumably sporadic) cases of KS are caused by defects in at least two autosomal genes that are currently unknown; 3) Obligate female carriers in families with KAL mutations have no discernible phenotype; 4) KAL mutations are uniformly absent in patients with either normosmic IHH or in families with both anosmic and nonanosmic individuals; and 5) Patients with KAL mutations have apulsatile LH secretion consistent with a complete absence of GnRH migration of GnRH cells into the hypothalamus, whereas evidence of present (but enfeebled) GnRH-induced LH pulses may be present in autosomal KS cases. Taken together, these findings suggest that autosomal genes account for the majority of familial cases of KS, and that unique neuroendocrine phenotypes consistent with some GnRH n...
Determining the physiologic influences that modulate GnRH secretion, the prime initiator of reproductive function in the human, is fundamental not only to our understanding of the rare condition of congenital idiopathic hypogonadotropic hypogonadism (IHH), but also common disorders such as constitutional delay of puberty and hypothalamic amenorrhea. IHH is characterized by low levels of sex steroids and gonadotropins, normal findings on radiographic imaging of the hypothalamic-pituitary regions, and normal baseline and reserve testing of the remainder of the hypothalamic-pituitary axes. Failure of the normal pattern of episodic GnRH secretion results in delay of puberty and infertility. IHH is characterized by rich clinical and genetic heterogeneity, variable modes of inheritance, and association with other anomalies. To date, 4 genes have been identified as causes of IHH in the human; KAL [the gene for X-linked Kallmann syndrome (IHH and anosmia)], DAX1 [the gene for X-linked adrenal hypoplasia congenita (IHH and adrenal insufficiency)], GNRHR (the GnRH receptor), and PC1 (the gene for prohormone convertase 1, causing a syndrome of IHH and defects in prohormone processing). As these mutations account for less than 20% of all IHH cases, discovery of additional gene mutations will continue to advance our understanding of this intriguing syndrome.
Mutations in the GnRH receptor (GNRHR) have been described as a cause of reproductive failure in a subset of patients with idiopathic hypogonadotropic hypogonadism (IHH). Given the apparent rarity of these mutations, we set out to determine the frequency and distribution of GNRHR mutations in a heterogeneous population of patients with IHH who were well characterized with respect to diagnosis, phenotype, and mode of inheritance and to define their distribution within the receptor protein. One hundred and eight probands with IHH were screened for mutations in the coding sequence of GNRHR. Forty-eight of the 108 patients had a normal sense of smell, whereas the remaining 60 had anosmia or hyposmia (Kallmann syndrome). Exon segments in the GNRHR were screened for mutations using temperature gradient gel electrophoresis, and all mutations were confirmed by direct sequencing. Five unrelated probands (3 men and 2 women), all normosmic, were documented to have changes in the coding sequence of the GNRHR. Two of these probands were from a subgroup of 5 kindreds consistent with a recessive mode of inheritance, establishing a GNRHR mutation frequency of 2 of 5 (40%) in patients with normosmic, autosomal recessive IHH. The remaining 3 probands with GNRHR mutations were from a subgroup of 18 patients without evidence of familial involvement, indicating a prevalence of 3 of 18 (16.7%) in patients with sporadic IHH and a normal sense of smell. Among the five individuals bearing GNRHR mutations, a broad spectrum of phenotypes was noted, including testicular sizes in the male that varied from prepubertal to the normal adult male range. Three probands had compound heterozygous mutations, and two had homozygous mutations. Of the eight DNA sequence changes identified, four were novel: Thr(32)Ile, Cys(200)Tyr, Leu(266)Arg, and Cys(279)TYR: COS-7 cells transiently transfected with complementary DNAs encoding the human GNRHR containing each of these four novel mutations failed to respond to GnRH agonist stimulation. We conclude that 1) the spectrum of phenotypes in patients with GNRHR mutations is much broader than originally anticipated; 2) the frequency of GNRHR mutations may be more common than previously appreciated in familial cases of normosmic IHH and infrequent in sporadic cases; and 3) functional mutations of the GNRHR are distributed widely throughout the protein.
The term DSD refers to disorders that affect the normal process of sexual development causing disagreement between chromosomal, gonadal and phenotypic sex, and this study aimed to describe the clinical profile of a group with DSD 46, XY joined on DSD Clinic of Hospital of Salvador, Bahia Clinics. It was a retrospective study of medical records of survey data of 93 patients with DSD 46, XY. Among the patients studied 50.5% had no defined etiology and 20.4% had androgen insensitivity syndrome (AIS), 63.4% had been initially recorded in males, 31 (33.3%) in females, being that in two it was necessary to reassignment. All patients with complete AIS pure gonadal dysgenesis and had female genitalia. Others have been diagnosed with genital ambiguity or severe hypospadias and cryptorchidism. The gonads were palpable at the first consultation in 75.3% of patients. It is important to establish an active surveillance program for these patients. The first assessment took place before the age of ten in more than 50% of cases, which shows that much needs to be done for medical education and community about the DSD. Because the phenotypic variability of sexual development disorders was noted that the clinical profile of patients studied ranged between different etiologies, including hindering the diagnostic conclusion of these individuals.
Kallmann syndrome (KS) consists of congenital, isolated, idiopathic hypogonadotropic hypogonadism (IHH) and anosmia. The gene responsible for the X-linked form of KS, KAL, encodes a protein, anosmin, that plays a key role in the migration of GnRH neurons and olfactory nerves to the hypothalamus. In addition to X-linked pedigrees, autosomal dominant and recessive kindreds with KS have been reported. The relative importance of these autosomal vs. X-linked genes in producing KS, and the frequency of KAL mutations, are currently unknown because these are rare disorders and large series are unusual. We examined 101 individuals with IHH (+/- anosmia) and their families to determine their modes of inheritance, incidence of mutations in the coding sequence of KAL, genotype-phenotype correlations, and [in a subset (n = 38)] their neuroendocrine phenotype. Of the 101 patients, 59 had true KS (IHH + anosmia/hyposmia); whereas, in the remaining 42, no anosmia was evident in the patients or their families. Of the 59 KS patients, 21 were familial, whereas 38 were sporadic cases. Mutations in the coding sequence of KAL were identified in only 3 of 21 familial cases (14%) and 4 of 38 (11%) of the sporadic cases. Of the X-linked cases confirmed by mutational analysis, only 1 of 3 pedigrees appeared X-linked by inspection whereas the other 2 contained only affected brothers. Female members of known KAL mutation families (n = 3) exhibited no reproductive phenotype and were not anosmic, whereas families with anosmic women (n = 3) were not found to carry mutations in KAL. Mutations were uniformly absent in nonanosmic IHH probands (n = 42), as well as in families with both anosmic and nonanosmic members (n = 2). Overall, 4 novel mutations were identified (C172R, R191x, R457x, and delC@L600). With respect to neuroendocrine phenotype, KS men with documented KAL mutations (n = 8) had completely apulsatile LH secretion, whereas those with autosomal modes of inheritance demonstrated a more variable spectrum with evidence of enfeebled (but present) GnRH-induced LH pulses. Our conclusions are: 1) Confirmed mutations in the coding sequence of the KAL gene occur in the minority of KS cases, i.e. only 14% of familial and 11% of sporadic cases; 2) The majority of familial (and presumably sporadic) cases of KS are caused by defects in at least two autosomal genes that are currently unknown; 3) Obligate female carriers in families with KAL mutations have no discernible phenotype; 4) KAL mutations are uniformly absent in patients with either normosmic IHH or in families with both anosmic and nonanosmic individuals; and 5) Patients with KAL mutations have apulsatile LH secretion consistent with a complete absence of GnRH migration of GnRH cells into the hypothalamus, whereas evidence of present (but enfeebled) GnRH-induced LH pulses may be present in autosomal KS cases. Taken together, these findings suggest that autosomal genes account for the majority of familial cases of KS, and that unique neuroendocrine phenotypes consistent with some GnRH neur...
RESUMOInformações recentes sugerem que o baixo peso ao nascer é uma variável importante para a ocorrência de obesidade e de componentes relacionados à síndrome metabólica, e que essas alterações podem ser detectadas, precocemente, na infância e adolescência. Alguns fatores relacionados ao feto e à mãe são mencionados na literatura como desencadeadores da prematuridade e subsequente baixo peso ao nascer. Os indivíduos com pequena idade gestacional têm alto risco de ganho de peso rápido no pós-natal, obesidade tardia e de apresentar alguns processos ligados a síndrome metabólica, como diabetes tipo 2, dislipidemia, hipertensão e doenças cardiovasculares. Conhecer o panorama dessas condições poderia contribuir para uma atenção precoce à saúde da criança com histórico de baixo peso ao nascimento com riscos à programação para essas doenças em longo prazo. O presente artigo teve como objetivo revisar as considerações atuais sobre a associação entre baixo peso ao nascer e a obesidade e síndrome metabólica na infância e adolescência. Palavras-chave: Recém-Nascido. Obesidade. Síndrome X metabólica. Criança. Adolescente. ABSTRACTRecent reports suggest that low birth weight is an important variable for the occurrence of obesity and related metabolic syndrome components, and that these changes can be detected early in childhood and adolescence. Some factors related to the fetus and mother are mentioned in the literature as causes of prematurity and subsequent low birth weight. Individuals with low gestational age are at high risk of rapid weight gain postnatally, later obesity and to present some processes related to metabolic syndrome and type 2 diabetes, dyslipidemia, hypertension and cardiovascular disease. Knowing of these conditions could contribute to an early attention of low birth weight infants at risk for these diseases to programming in the long term. This review article aimed to research current considerations on the association between low birth weight and obesity and metabolic syndrome in childhood and adolescence. Keywords:: Infant newborn. Obesity. Metabolic Syndrome X. Child. Adolescent. INTRODUÇÃOO baixo peso ao nascer (BPN) é considerado um dos grandes problemas de saúde pública, especialmente no Brasil, devido ao impacto sobre a morbidade e mortalidade infantil. A prematuridade e a restrição do crescimento intra-uterino (RCIU) têm sido apontadas como as maiores responsáveis por essa condição. A inter-relação dessas variáveis forma um quadro significativo de riscos às doenças, além de poder levar a morte no primeiro ano de vida.No Brasil, informações mais recentes do Ministério da Saúde revelam que, do total de nascidos de BPN em 2007, 7,8% correspondeu ao parto normal e 8,6% ao cesáreo. Ao comparar os levantamentos de 2000 a 2007, verifica-se que houve importante aumento de BPN nos nascidos de parto cesáreo (BRASIL, 2009).Sabe-se que o tamanho ao nascimento é o resultado do crescimento fetal, e este deve ser considerado como uma condição adequada para a vida pós-natal. Este processo complexo depende de i...
Goals To investigate the effect of COX-2 polymorphism and its product, prostaglandin-E2 (PGE2), on stroke risk in an endemic area for Chagas disease. In a separate cohort, to investigate the effect of COX-2 polymorphisms on the total burden of cerebral white matter disease. Methods Cases were outpatients with ischemic stroke; controls were stroke-free subjects from two outpatient clinics (heart failure and caregivers of a movement disorders clinic). We extracted DNA from total blood to investigate the rs20417 COX-2 polymorphism. Serologic tests (ELISA) were performed to confirm T. cruzi infection and to quantify PGE2 levels. In the Boston cohort, white matter hyperintensity volume (WMHv) was quantified on the admission brain MRIs of subjects with ischemic stroke, who also donated DNA for the COX-2 gene region analysis. Findings We studied 44 patients with stroke and 96 controls (46 with heart failure and 50 caregivers) in the Brazilian cohort; and 788 stroke patients (302 cardioembolic, 486 non-cardioembolic) in the Boston cohort. In the Brazilian cohort, rs20417 polymorphism was associated with both stroke (p=5x10−6) and decreased PGE2 levels (p=4x10−5); similarly, Chagas was associated with stroke (p=4x10−3) and decreased PGE2 levels (p=7x10−3). In the Boston cohort, rs20417 polymorphism was associated with increased WMHv among non-cardioembolic (p=0.037), but not among cardioembolic stroke patients. Conclusions Variation in COX-2 gene is associated with both symptomatic and silent brain cerebrovascular disease. This candidate gene region should be tested in population-based samples.
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