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Background: The 5α-reductase type 2 (5α-RD2) deficiency caused by mutations in the steroid 5α-reductase 2 ( SRD5A2 ) gene results in variable degrees of undervirilisation in patients with 46,XY disorders of sex development. This study aims to profile the regional distribution and phenotype-genotype characteristics of SRD5A2 in a large Chinese 5α-RD2 deficiency cohort through multi-centre analysis., Methods: 190 subjects diagnosed with 5α-RD2 deficiency were consecutively enrolled from eight medical centres in China. Their clinical manifestations and genetic variants were analysed., Results: Hypospadias (isolated or combined with microphallus and/or cryptorchidism) was fairly common in the enrolled subjects (66.32%). 42 variants, including 13 novel variants, were identified in SRD5A2 . Homozygous and compound heterozygous mutations presented in 38.42% and 61.58% of subjects, respectively, and predominated in exons 1, 4 and 5. The most prevalent variant was c.680G > A (52.37%), followed by c.16C > T, (10.79%), c.607G > A, (9.21%) and c.737G > A, (8.95%). However, their distributions were different: c.680G > A was more common in South China than in North China (62.62% vs 39.16%, p < 0.001), whereas the regional prevalence of c.16C > T was reversed (6.07% vs 16.87%, p = 0.001). Furthermore, c.680G > A prevailed in cases with normal meatus (68.75%) or distal hypospadias (66.28%), compared with those with proximal hypospadias (35.54%, p < 0.001). However, cases with proximal hypospadias showed a higher frequency of c.16C > T (20.48%) than those with normal meatus (3.13%) or distal hypospadias (3.49%, p < 0.001)., Conclusions: This study profiled variable phenotypic presentation and wide mutational spectrum of SRD5A2, revealing its distinctive regional distribution in Chinese patients and further shaping the founder effect and genotype-phenotype correlation of SRD5A2 ., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Opitz G/BBB syndrome is a heterogeneous disorder characterised by variable expression of midline defects including cleft lip and palate, hypertelorism, laryngealtracheoesophageal anomalies, congenital heart defects, and hypospadias. The X-linked form of the condition has been associated with mutations in the MID1 gene on Xp22. The autosomal dominant form has been linked to chromosome 22q11.2, although the causative gene has yet to be elucidated., Methods and Results: In this study, we performed whole exome sequencing on DNA samples from a three-generation family with characteristics of Opitz G/BBB syndrome with negative MID1 sequencing. We identified a heterozygous missense mutation c.1189A>C (p.Thr397Pro) in SPECC1L, located at chromosome 22q11.23. Mutation screening of an additional 19 patients with features of autosomal dominant Opitz G/BBB syndrome identified a c.3247G>A (p.Gly1083Ser) mutation segregating with the phenotype in another three-generation family., Conclusions: Previously, SPECC1L was shown to be required for proper facial morphogenesis with disruptions identified in two patients with oblique facial clefts. Collectively, these data demonstrate that SPECC1L mutations can cause syndromic forms of facial clefting including some cases of autosomal dominant Opitz G/BBB syndrome and support the original linkage to chromosome 22q11.2., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

We have reviewed all known UK cases of Smith-Lemli-Opitz syndrome. Among 49 cases with proven 7-dehydrocholesterol reductase deficiency, half had been terminated or had died in infancy. The minimum incidence is 1 in 60,000. The frequent occurrence of hypospadias may account for 71% of recognised cases being male. Important common features which emerged include short thumbs, severe photosensitivity, aggressive behaviour, and atrioventricular septal defect. The typical facial appearance becomes less obvious with age and 20% of cases did not have 2/3 toe syndactyly. Biochemical measurements of serum 7-dehydrocholesterol did not correlate with clinical severity.

We report on two severely mentally retarded male children of consanguineous parents who seem to be affected by an identical syndrome. The main physical anomalies are typical facial stigmata with a broad nasal bridge, a bulbous nose, upward slanting palpebral fissures, microretrognathia, low hair line, and large ears with an incompletely developed upper helix. In addition, both brothers had hypospadias type II, limb contractures, and delayed bone age. One child had a bilateral cleft lip with cleft palate and cryptorchidism, and developed scoliosis during adolescence. The other had bilateral inguinal hernias and strabismus. Chromosome analysis showed a normal karyotype in both. The striking similarity between the brothers, the dissimilarity to other known syndromes, and the parental consanguinity argue in favour of a new, hitherto undescribed, possibly autosomal recessive syndrome.

Hypospadias is a common urological abnormality and may occur in simple (glandular or penile) or severe forms (perineal). Perineal hypospadias often occurs in association with other genital abnormalities, such as bilateral cryptorchidism and micropenis, and may be the result of partial androgen insensitivity. We have investigated the androgen binding status and androgen receptor gene of boys from two unrelated families. The first pair of brothers had partial androgen insensitivity with perineal hypospadias, bilateral cryptorchidism, and micropenis, while the other boys had isolated perineal hypospadias. Qualitative androgen binding defects were shown in both sets of brothers and different point mutations of the androgen receptor gene were found in the two families. These findings suggest that the genital abnormalities in the affected brothers result from defects in the androgen receptor. Furthermore, severe familial hypospadias may be a previously unrecognised part of the phenotypic spectrum of the partial androgen insensitivity syndrome. This study provides valuable information for the genetic counselling of families affected by this X linked genital abnormality.

A case control study of hypospadias was performed from 1979 to 1987 in Alsace, north-eastern France. A total of 176 out of 60 847 male infants had hypospadias giving a prevalence at birth of 2.89 per 1000 male newborns; 15.3% of all infants with hypospadias also had other malformations. Renal and urinary tract malformations were present in 37.0% of the infants with hypospadias and other additional malformations. None of the numerous aetiological factors which were studied was correlated with hypospadias except low weight of the placenta. The recurrence risk for brothers was 17.0% (an empirical risk of about 1 in 6) and the heritability coefficient was 56.9%. First degree relatives of infants with hypospadias had more malformations other than hypospadias than controls. These results have to be taken into consideration for genetic counselling.

Epidemiological and genetic variables in hypospadias were analysed during the years 1978 to 1983 in a case control study of congenital malformations in the Emilia Romagna region of northern Italy. During the observation period, in a sample of 41 078 male newborns, 168 had hypospadias giving a prevalence at birth of 4.1 in 1000 males. Hypospadias was divided into three types: type I or mild (75.0%); type II or moderate (21.4%); and type III or severe (3.6%). Coexisting malformations were found in 8.9% of cases. The heritability coefficient was 0.669. Maternal risk factors correlated with hypospadias were found to be early age at menarche, threatened abortion, and exposure to progestins. Low birth weight and shorter gestation were also correlated with hypospadias.

Three families including five subjects with the G or Opitz-Frias syndrome are added to 23 published cases who had dysphagia; characteristics of the two affected relatives were added to 19 well documented published reports. The data from index cases support the concept of the G syndrome as a constellation of midline defects, which include hypertelorism or telecanthus (89%), oesophageal dysmotility (69%), laryngotracheal clefts (44%), cleft palate or bifid uvula (34%), heart defects (29%), hypospadias (100% of males), renal or ureteral anomalies (42%), and mental retardation (38%). Affected relatives, often identified by hypertelorism, dysphagia, or hypospadias, had a much lower incidence of associated defects and mental retardation. They provide a more rounded but still biased view of a syndrome compatible with normal intelligence and life span. The data do not support a highly characteristic face in the G syndrome, which discriminates it from the phenotypically similar BBB syndrome. The variable expressivity and five cases of male to male transmission observed in 18 families are consistent with autosomal dominant inheritance. Vigilance for the morphological characteristics of G syndrome in patients with dysphagia is underscored by the potential for normal development with appropriate intervention.

Two brothers with severe and rare lower limb malformations but normal upper limbs are described. Both brothers had glans hypospadias and they died in early infancy. In the first brother the limb malformation was a severe deformity of the right foot which was split and of rockerbottom shape with oligosyndactyly. In the second brother the right limb below the knee was more severely deformed while only the toes were involved in the left limb. Details of the clinical and pathological findings are described. The most likely mode of inheritance of this rare syndrome is autosomal recessive or X-linked recessive with variable expressivity.

The telecanthus-hypospadias (BBB) syndrome is characterised by widely spaced inner ocular canthi and hypospadias of variable degree. Heterozygous females have telecanthus. We have summarised the historical and phenotypic findings of 21 patients in seven previous publications. We have also had the opportunity to evaluate personally 12 families with a total of 18 affected males. The most frequent anomalies in patients previously reported are telecanthus 21/21, hypospadias 19/21, cleft lip/palate or uvula 7/21, high, broad nasal bridge 15/15, cranial abnormality 6/21, congenital heart defect 5/21, cryptorchidism 9/21, and mental retardation 11/17. In our series, the most frequent anomalies include telecanthus 18/18, hypospadias 18/18, cleft lip/palate or uvula 8/18, high, broad nasal bridge 10/11, cranial abnormality 12/18, congenital heart defect 3/18, upper urinary tract anomaly 4/9, and mental retardation 10/12. There is also an increased incidence of like-sex twinning, 11/18 in our families. This syndrome must be more common than reflected in published reports. Based upon the observation that males are much more severely affected than females and the lack of male to male transmission, it appears that this condition is most likely to be inherited in an X linked fashion. Further elucidation of the phenotype and documentation of the inheritance is needed. The distinction between the telecanthus-hypospadias syndrome and the G syndrome also needs further clarification.

A new syndrome characterized by cleft palate, coloboma, hypospadias, deafness, short stature, and radial synostosis has been described. The family history suggests either an autosomal dominant mode of inheritance with limited expression in females or X-linkage. Other syndromes with similar phenotypes and modes of inheritance are discussed. The need for accurate and complete family histories in cases involving cleft palate and cleft lip/palate is discussed in relation to genetic counselling and recurrent risk estimates.

We have identified a partial deletion of the long arm of chromosome 7 in a newborn baby boy. His major anomalies were microcephaly, synbrachydactyly, diastisis recti, hypospadias, short neck, and widely spaced nipples.