Polycystic ovary syndrome: a component of metabolic syndrome?

In 1935, Stein and Leventhal first described the polycystic ovary (PCO) as a frequent cause of irregular ovulation in women seeking treatment for subfertility. Although the initial management was surgical with wedge resection of ovary, the availability of radioimmunoassay and increased clinical use of ultrasound made it clear that many women had the ultrasound characteristics of PCO with or without the biochemical or clinical features of PCOS and therefore that PCO were not associated with a single syndrome. The association between increased insulin resistance and PCOS is a consistent finding in all ethnic groups. Obesity is a common factor in the majority of women with PCOS. It is postulated that a woman may be genetically predisposed to developing PCOS but it is only the interaction of environmental factors (obesity) with the genetic factors that results in the characteristic metabolic and menstrual disturbances. Weight loss, altered diet and exercise have been shown to be effective in the management of PCOS. Importance of early recognition, proper intervention, long-term monitoring and health implications needs more concern.     

Tetrasomy 15q26: a distinct syndrome or Shprintzen-Goldberg syndrome phenocopy?

PurposeThe aim of this study was to characterize the clinical phenotype of patients with tetrasomy of the distal 15q chromosome in the form of a neocentric marker chromosome and to evaluate whether the phenotype represents a new clinical syndrome or is a phenocopy of Shprintzen-Goldberg syndrome.MethodsWe carried out comprehensive clinical evaluation of four patients who were identified with a supernumerary marker chromosome. The marker chromosome was characterized by G-banding, fluorescence in situ hybridization, single nucleotide polymorphism oligonucleotide microarray analysis, and immunofluorescence with antibodies to centromere protein C.ResultsThe marker chromosomes were categorized as being neocentric with all showing tetrasomy for regions distal to 15q25 and the common region of overlap being 15q26→qter.ConclusionTetrasomy of 15q26 likely results in a distinct syndrome as the patients with tetrasomy 15q26 share a strikingly more consistent phenotype than do the patients with Shprintzen-Goldberg syndrome, who show remarkable clinical variation.Genet Med 2012:14(9):811–818     

Acro-cardio-facial syndrome: a microdeletion syndrome?

Acro-cardio-facial syndrome (ACFS) is an infrequently reported, variable condition characterized by split-hand and split-foot malformation and congenital heart defect (CHD), along with cleft lip and palate, genital anomalies, unusual face and intellectual disability. An autosomal recessive pattern of inheritance has been suggested because of affected sibs born to unaffected parents and parental consanguinity; the cause is unknown. We describe a newborn with the clinical manifestations of ACFS in whom a deletion of the region 6q21-q22.3 was detected by array CGH. We compare the clinical features of the present patient with earlier reported patients with similar 6q deletions and patients diagnosed with ACFS. The similarities between these patient groups suggest that ACFS may be a microdeletion syndrome caused by loss of the 6q21-22.3 region. The recurrence in families may be explained by prenatal germline mosaicism. Alternatively, ACFS may be a genetically heterogeneous disorder which can also be caused by biallelic mutations of an autosomal recessive gene.     

Klippel-Feil anomaly with Sprengel anomaly, omovertebral bone, thumb abnormalities, and flexion-crease changes: novel association or syndrome?

We report on a family with Klippel-Feil anomaly (KF), Sprengel anomaly, omovertebral bone, thumb abnormalities, and flexion-crease abnormalities. This combination of abnormalities does not fit into Holt-Oram syndrome, Wildervanck syndrome, oculo-auriculo-vertebral (Goldenhar) anomaly, or the VATER complex. Clinical aspects of a KF classification are discussed. The state of molecular research on KF is briefly reported. We conclude that this set of anomalies is a novel combination, probably representing pleiotropy of a single Mendelian gene.     

Is it a new syndrome or a clinical variability in cerebro-oculo-nasal syndrome?

We present a male infant 2.5-months old with asymmetric skull, anophthalmia, apparent hypertelorism, abnormal nares, unilateral cleft lip and palate, and structural abnormalities of the central nervous system. These findings are similar to cerebro-oculo-nasal syndrome except for the appearance of nose. This case is either a clinical variability in cerebro-oculo-nasal syndrome or a new entity.     

Scimitar vein anomaly with multiple cardiac malformations,craniofacial, and central nervous system abnormalities in a brother and sister: familial scimitar anomaly or new syndrome?

The scimitar vein "syndrome" is an anomaly of lobar aplasia or hypoplasia and total or partial anomalous venous drainage of one lung. We report a brother and sister born to nonconsanguineous Italian parents with a fatal infantile form of scimitar vein anomaly associated to multiple cardiac anomalies. The infants had major craniofacial anomalies. In addition, the boy had iris coloboma and enlarged cisterna magna; both sibs showed poor brain myelination at neuroimaging confirmed by histopathology in the girl. The cardiovascular system in the family members was fully investigated and all results were completely normal. The association of the above craniofacial anomalies has been occasionally mentioned in syndromes with anomalous venous return. The familial occurrence of isolated total anomalous pulmonary venous return has been documented in sibs, first cousins, and through consecutive generations. Familial pulmonary hypoplasia, as an isolated finding, has been observed in siblings and twins. To the best of our knowledge, even though five familial cases of scimitar "syndrome" have been described thus far, the constellation of anomalies shown by these two sibs has not been reported previously. It appears that scimitar vein "syndrome" is not a "syndrome" per se: it is most likely an anomaly of heterogeneous etiology. This family may represent its own novel syndrome of multiple congenital anomalies of which scimitar vein is a component.     

Proinsulin serum concentrations in women with polycystic ovary syndrome: a marker of beta-cell dysfunction?

BACKGROUND: The aim of this study was to establish the effect of polycystic ovary syndrome (PCOS) adjusted for adiposity on proinsulin concentrations. METHODS: Ninety-one women with PCOS and 72 normal cycling (NC) women were recruited. A 2 h, 75 g oral glucose tolerance test was performed. Glucose and insulin were measured in each sample. Proinsulin and C-peptide were determined at 0 and 30 min and the fasting proinsulin/insulin ratio (PI/I) was calculated. Insulin sensitivity was estimated by insulin sensitivity index (ISI) composite, and beta-cell function was estimated by insulinogenic index. RESULTS: Insulin, proinsulin and C-peptide concentrations were higher in women with PCOS than in NC women (P < 0.05). PI/I and insulinogenic index were similar in both groups. Proinsulin concentrations increased with body mass index (P < 0.05) only in women with PCOS; therefore, proinsulin concentrations were higher in obese PCOS patients compared with obese control women (P < 0.05). Moreover, a positive association between proinsulin concentrations and waist diameter adjusted for C-peptide (P < 0.05) and a negative association between proinsulin concentrations and ISI composite values were observed in PCOS patients (P < 0.05). CONCLUSIONS: Data suggest that in PCOS patients an elevated proinsulin concentration could reflect insulin resistance more than beta-cell dysfunction. However, the elevated concentration of proinsulin in these patients could also result from impaired beta-cell function resulting from intra-abdominal obesity independently of insulin resistance.     

Say-Barber-Biesecker-Young-Simpson syndrome and Genitopatellar syndrome: Lumping or splitting?

The Say-Barber-Biesecker-Young-Simpson variant of Ohdo syndrome (SBBYSS) and Genitopatellar syndrome (GTPTS) are 2 rare but clinically well-described diseases caused by de novo heterozygous sequence variants in the KAT6B gene. Both phenotypes are characterized by significant global developmental delay/intellectual disability, hypotonia, genital abnormalities, and patellar hypoplasia/agenesis. In addition, congenital heart defects, dental abnormalities, hearing loss, and thyroid anomalies are common to both phenotypes. This broad clinical overlap led some authors to propose the concept of KAT6B spectrum disorders. On the other hand, some clinical features could help to differentiate the 2 disorders. Furthermore, it is possible to establish a genotype-phenotype correlation when considering the position of the sequence variant along the gene, supporting the notion of the 2 disorders as really distinct entities.     

Autosomal dominant macrocephaly: benign familial macrocephaly or a new syndrome?

During the course of a clinical study of Sotos syndrome, six out of 79 probands failed to fit the phenotype of Sotos syndrome but showed remarkable similarities to each other and to a further 11 first- and second-degree relatives. Clinical features in these index cases included macrocephaly, greater than +3.5 SD; normal or near normal birth weight and length with subsequent relative obesity; variable developmental delay; and typical face, characterised by a square outline with frontal bossing, a "dished-out" mid-face, biparietal narrowing, and long philtrum. All recorded bone ages were less than the 75th centile, and two were below the 10th centile. The authors believe the original diagnosis was incorrect and that these cases likely represent a previously undescribed autosomal dominant macrocephaly syndrome.     

Androgen excess fetal programming of female reproduction: a developmental aetiology for polycystic ovary syndrome?

The aetiology of polycystic ovary syndrome (PCOS) remains unknown. This familial syndrome is prevalent among reproductive-aged women and its inheritance indicates a dominant regulatory gene with incomplete penetrance. However, promising candidate genes have proven unreliable as markers for the PCOS phenotype. This lack of genetic linkage may represent both extreme heterogeneity of PCOS and difficulty in establishing a universally accepted PCOS diagnosis. Nevertheless, hyperandrogenism is one of the most consistently expressed PCOS traits. Animal models that mimic fetal androgen excess may thus provide unique insight into the origins of the PCOS syndrome. Many female mammals exposed to androgen excess in utero or during early post-natal life typically show masculinized and defeminized behaviour, ovulatory dysfunction and virilized genitalia, although behavioural and ovulatory dysfunction can coexist without virilized genitalia based upon the timing of androgen excess. One animal model shows particular relevance to PCOS: the prenatally androgenized female rhesus monkey. Females exposed to androgen excess early in gestation exhibit hyperandrogenism, oligomenorrhoea and enlarged, polyfollicular ovaries, in addition to LH hypersecretion, impaired embryo development, insulin resistance accompanying abdominal obesity, impaired insulin response to glucose and hyperlipidaemia. Female monkeys exposed to androgen excess late in gestation mimic these programmed changes, except for LH and insulin secretion defects. In utero androgen excess may thus variably perturb multiple organ system programming and thereby provide a single, fetal origin for a heterogeneous adult syndrome.     

Motor unit double discharges: statistical anomaly or functional entity?

Motor unit double discharges, or doublets, have been described as two consecutive motor unit discharges that occur with a short interspike interval of 2.5 - 20 ms (Simpson, 1969). Double discharges have been reported in the literature for over 70 years. For instance, Eccles and Hoff (1932) found that double discharges were elicited occasionally at the onset of a crossed extension reflex in the soleus muscle of the anaesthetized cat. With the use of electrical stimulation protocols, short interspike intervals inserted at the beginning of a stimulation train have been shown to increase both the peak force and rate of rise of force production, and also decrease the range of fatigue. The extent to which double discharges occur in naturally-occurring voluntary behaviours remains relatively unexplored. This review examines the issue of whether double discharges occur solely because of an intrinsic property of motoneurones, thereby representing a "statistical anomaly," or whether they may result from a neural control strategy to augment force production, i.e., a "functional entity."     

Proximal 1q21 duplication: A syndrome or a susceptibility locus?

Proximal 1q21 microduplication is an incomplete penetrance and variable expressivity syndrome. This study reports 28 new cases and summarizes data on phenotype, gender, and parental origin. Data on isolated proximal 1q21.1 microduplications (g. chr1:145,394,956–145,762,959 GRCh37/hg19) was retrieved in postnatal and prenatal “clinical cases” group, and prenatal “control group.” The “clinical cases” cases included cases where chromosomal microarray (CMA) was performed due to congenital anomalies, autism spectrum disorder, seizures, and developmental delay/intellectual disability. The “control group” cases consisted of fetal CMA performed upon parental request despite normal nuchal translucency and anatomical second trimester fetal scans. We analyzed a local database of 27,990 cases and another cohort of 80,000 cases (including both indicated and non-indicated cases) for population frequency analysis. A total of 62 heterozygous cases were found, including 28 index cases and 34 family members. Among the index cases, 13 (9 males, 4 females) were identified in the “clinical cases” group, of which 10 had developmental abnormalities. Parental origin was tested in 9/13 cases, and all were found to be maternally inherited. In the “control group,” which comprised non-affected cases, of 15 cases (10 males, 5 females), only 5/11 were maternally inherited. Four cases with clinical follow-up showed no reported neurodevelopmental abnormalities. No de-novo cases were detected, and the population frequency in both cohorts was 1:1000. Proximal 1q21.1 microduplication is a recurrent copy number variant, associated with neurodevelopmental abnormalities. It has a greater impact on males inheriting it from their mothers than females from their fathers.     

Surrogate end-points or primary outcomes in clinical trials in women with polycystic ovary syndrome?

There are multiple surrogate variables in polycystic ovary syndrome (PCOS), including biometric and biochemical parameters. The number of surrogate variables and their poor validity in relationship to primary clinical end-points pose major problems to conducting a trial in women with PCOS. The aim of this review is to discuss the use of surrogate variables compared with primary clinical end-points in women with PCOS. Arguably the best documented correlation between a surrogate variable and a primary clinical end-point is that between ovulation and pregnancy in women with PCOS. Good correlation has been noted between the increase in ovulation frequency with clomiphene citrate and the chance of pregnancy in women with PCOS. However, ovulation cannot be equated with pregnancy, as a host of other factors may affect the true outcome of interest: a healthy liveborn child. Pregnancy and an improvement in hirsutism are clinical end-points that have been successfully studied in past and ongoing clinical trials in women with PCOS. Many other clinical end-points, such as endometrial cancer and cardiovascular disease, are rare in premenopausal women with PCOS, and may not be suitable as the primary outcome of clinical studies. Future multicentre trials in women with PCOS should focus on primary clinical end-points.     

Developmental dyscalculia: a dysconnection syndrome?

Numerical understanding is important for everyday life. For children with developmental dyscalculia (DD), numbers and magnitudes present profound problems which are thought to be based upon neuronal impairments of key regions for numerical understanding. The aim of the present study was to investigate possible differences in white matter fibre integrity between children with DD and controls using diffusion tensor imaging. White matter integrity and behavioural measures were evaluated in 15 children with developmental dyscalculia aged around 10 years and 15 matched controls. The main finding, obtained by a whole brain group comparison, revealed reduced fractional anisotropy in the superior longitudinal fasciculus in children with developmental dyscalculia. In addition, a region of interest analysis exhibited prominent deficits in fibres of the superior longitudinal fasciculus adjacent to the intraparietal sulcus, which is thought to be the core region for number processing. To conclude, our results outline deficient fibre projection between parietal, temporal and frontal regions in children with developmental dyscalculia, and therefore raise the question of whether dyscalculia can be seen as a dysconnection syndrome. Since the superior longitudinal fasciculus is involved in the integration and control of distributed brain processes, the present results highlight the importance of considering broader domain-general mechanisms in the diagnosis and therapy of dyscalculia.     

What is polycystic ovary syndrome? Are national views important?

Polycystic ovary syndrome (PCOS) is a true syndrome, being a heterogeneous collection of signs and symptoms that gathered together form a spectrum of a disorder with a mild presentation in some, whilst in others there is a severe disturbance of reproductive, endocrine and metabolic function. There has been much debate about phenotype and, more recently, genotype. There has also been scepticism in some quarters, with a feeling that we may be looking at one end of a spectrum that is in reality 'normal', or perhaps a consequence of the modern disease of obesity. Whilst the polycystic ovary is at the centre of the syndrome, it is external effects such as hyperinsulinism, that influence its expression. There is no consensus on the definition of PCOS and so studies that compare epidemiology and treatments often have very different starting points, and so cannot be compared. In this debate we wish to re-explore our current thinking on PCOS, with a particular emphasis on the British and European perspective and invite others to contribute to the discussion which could form the basis for an international consensus.     

Familial Axenfeld-Rieger anomaly,cardiac malformations,and sensorineural hearing loss: a provisionally unique genetic syndrome?

Axenfeld-Rieger anomaly (ARA) is an autosomal dominant disorder of the anterior chamber of the eye that includes a prominent and anteriorly displaced Schwalbe line and an iridocorneal synechiae, and is associated with iris hypoplasia, corectopia, and hole formation. Extraocular developmental abnormalities, especially of the teeth, facial bones, and periumbilical skin, have also been reported with ARA, in the context of the so-called Axenfeld-Rieger syndrome (ARS). Genetic heterogeneity exists, as ARA maps to chromosome 6p25, whereas ARS can be linked to both chromosome 4q25 and chromosome 13q14. Here we describe a new family in which ARA is associated with cardiac malformations and sensorineural hearing loss. No abnormalities of the teeth, facial bone, or periumbilical skin, which are considered of paramount importance in the diagnosis of ARS, were observed in our patients. Genetic studies will clarify if these patients represent a unique phenotypic expression of ARS or constitute the clinical presentation of a new genetic syndrome.