Opitz syndrome is genetically heterogeneous, with one locus on Xp22, and a second locus on 22q11.2.

Opitz syndrome (OS, McKusick 145410) is a well described genetic syndrome affecting multiple organ systems whose cardinal manifestations include widely spaced eyes and hypospadias (Fig. 1). It was first reported as two separate entities, BBB syndrome, and G syndrome. However, subsequent reports of families in which the BBB and G syndrome segregated within a single kindred suggested that they were a single clinical entity. Although the original pedigrees were consistent with X-linked and autosomal dominant inheritance, male-to-male transmission in subsequent reports suggested that OS was inherited as an autosomal dominant trait. Here we report that OS is a heterogeneous disorder, with an X-linked and an autosomal locus. Three families were linked to DXS987 in Xp22, with a lod score of 3.53 at zero recombination. Five families were linked to D22S345 from chromosome 22q11.2, with a lod score of 3.53 at zero recombination. This represents the first classic multiple congenital anomaly syndrome with an X-linked and an autosomal form.

Face-brain asymmetry in autism spectrum disorders.

The heterogeneity of autism spectrum disorders (ASDs) confounds attempts to identify causes and pathogenesis. Identifiable endophenotypes and reliable biomarkers within ASDs would help to focus molecular research and uncover genetic causes and developmental mechanisms. We used dense surface-modelling techniques to compare the facial morphology of 72 boys with ASD and 128 first-degree relatives to that of 254 unrelated controls. Pattern-matching algorithms were able to discriminate between the faces of ASD boys and those of matched controls (AUC=0.82) and also discriminate between the faces of unaffected mothers of ASD children and matched female controls (AUC=0.76). We detected significant facial asymmetry in boys with ASD (P<0.01), notably depth-wise in the supra- and periorbital regions anterior to the frontal pole of the right hemisphere of the brain. Unaffected mothers of children with ASD display similar significant facial asymmetry, more exaggerated than that in matched controls (P<0.03) and, in particular, show vertical asymmetry of the periorbital region. Unaffected fathers of children with ASD did not show facial asymmetry to a significant degree compared to controls. Two thirds of unaffected male siblings tested were classified unseen as more facially similar to unrelated boys with ASD than to unrelated controls. These unaffected male siblings and two small groups of girls with ASD and female siblings, all show overall directional asymmetry, but without achieving statistical significance in two-tailed t-tests of individual asymmetry of ASD family and matched control groups. We conclude that previously identified right dominant asymmetry of the frontal poles of boys with ASD could explain their facial asymmetry through the direct effect of brain growth. The atypical facial asymmetry of unaffected mothers of children with ASD requires further brain studies before the same explanation can be proposed. An alternative explanation, not mutually exclusive, is a simultaneous and parallel action on face and brain growth by genetic factors. Both possibilities suggest the need for coordinated face and brain studies on ASD probands and their first-degree relatives, especially on unaffected mothers, given that their unusual facial asymmetry suggests an ASD susceptibility arising from maternal genes.

Further delineation of cardio-facio-cutaneous syndrome: clinical features of 38 individuals with proven mutations.

BACKGROUND: Cardio-facio-cutaneous syndrome (CFC) is a multiple congenital anomaly/mental retardation syndrome named because of a characteristic facies, cardiac anomalies, and ectodermal abnormalities. While considerable literature describes the main features, few studies have documented the frequencies of less common features allowing a greater appreciation of the full phenotype. METHODS: We have analysed clinical data on 38 individuals with CFC and a confirmed mutation in one of the genes known to cause the condition. We provide data on well-established features, and those that are less often described. RESULTS: Polyhydramnios (77%) and prematurity (49%) were common perinatal issues. 71% of individuals had a cardiac anomaly, the most common being pulmonary valve stenosis (42%), hypertrophic cardiomyopathy (39%), and atrial septal defect (28%). Hair anomalies were also typical: 92% had curly hair, 84% sparse hair, and 86% absent or sparse eyebrows. The most frequent cutaneous features were keratosis pilaris (73%), hyperkeratosis (61%) and nevi (76%). Significant and long lived gastrointestinal dysmotility (71%), seizures (49%), optic nerve hypoplasia (30%) and renal anomalies, chiefly hydronephrosis (20%), were among the less well known issues reported. CONCLUSION: This study reports a broad range of clinical issues in a large cohort of individuals with molecular confirmation of CFC.

Neuropathy in Navajo children: clinical and epidemiologic features.

We describe a rare and apparently unique neuropathic syndrome among Navajo children living on the Navajo Reservation. Clinical features include sensorimotor neuropathy, corneal ulcerations, acral mutilation, poor weight gain, short stature, sexual infantilism, serious systemic infections, and liver derangement including Reye's syndrome-like episodes. Progressive CNS white matter lesions were diagnosed through magnetic resonance imaging. We identified 20 definite and 4 probable cases occurring between 1959 and 1986. Mean age at the time of 1st recognized symptom was 13 months (range, 1 month to 4 years 6 months). Ten individuals have died; 6 of the deaths occurred before 5 years of age. The incidence of this syndrome on the western Navajo reservation is 5 times higher than that on the eastern reservation (38 compared with 7 cases per 100,000 births). Although the etiology is unknown, this syndrome is consistent with an inborn error of metabolism, inherited in an autosomal recessive manner.

Prenatal cocaine exposure and fetal vascular disruption.

The question of the potential teratogenicity of cocaine has been raised by the increasing frequency of its abuse in the United States. In previous studies, an increased incidence has been documented of spontaneous abortion, placental abruption, prematurity, intrauterine growth retardation, and neurologic deficits in the infants of women who abused cocaine. More recently, it has been suggested in studies that fetal vascular disruption accompanying maternal cocaine abuse may lead to cavitary central nervous system lesions and genitourinary anomalies. In this article, 10 children born of women who abused cocaine are described, 9 of whom have congenital limb reduction defects and/or intestinal atresia or infarction. The spectrum of anomalies associated with embryonic and fetal vascular disruption accompanying maternal cocaine abuse is thus enlarged. The specific risk for congenital anomalies accompanying maternal cocaine abuse during an individual pregnancy is unknown. However, data from these patients and the available literature suggest that counseling pregnant women concerning cocaine use should incorporate warnings about the possibility of associated embryonic or fetal vascular disruption.

G syndrome: an unusual family.

The G syndrome is a multiple congenital anomaly (MCA) syndrome of hypertelorism, hypospadias, stridor, and swallowing difficulties. Cleft lip and palate, cardiac defects, cranial asymmetry, and bowel obstruction are occasional manifestations. Family data suggest autosomal dominant inheritance. Males appear to have more serious manifestations, whereas most females with the G syndrome have a benign course and are ascertained through affected male relatives. In the family reported here, the proposita was first seen at age 7 weeks because of swallowing difficulties, stridor, and unusual facial appearance, reminiscent of the G syndrome. Evaluation of the family showed striking facial changes in her father and all four of his sibs. These five individuals had megalencephaly, hypertelorism, and a broad prominent nasal root and bridge, reminiscent of the facial appearance in the BBB syndrome. There was no evidence for dysphagia, respiratory abnormality, or hoarse voice in any other relative. These individuals with the G syndrome display two unusual manifestations. There are no males with hypospadias; the proposita has the most severe laryngotracheoesophageal symptoms. Although hypospadias is not an invariable manifestation of the G syndrome and although six females with severe dysphagia or respiratory abnormalities have been reported previously, the manifestations in this family underline the variability of this condition and provide further support that the G syndrome can be expressed with equal severity in both males and females. Although phenotypic overlap between the BBB and G syndromes has long been recognized, many still consider them to be distinct nosologic entities. The occurrence of both BBB and G syndrome in different members of the same family has been observed previously.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective techniques for craniofacial assessment: what are the choices?

The approach to an individual with unusual facial appearance has traditionally involved a subjective assessment coupled with a few craniofacial measurements. Our ability to describe facial morphology has improved in recent years through the development of new techniques such as computerized tomography, magnetic resonance imaging, ultrasound studies, and stereoscopic imaging. However, the relatively simpler techniques of anthropometry, cephalometry, and photogrammetry, developed prior to the advent of microchips and imaging software, continue to provide unique advantages not afforded by these technically more sophisticated methods. These objective methods should enhance pattern recognition, particularly in rare syndromes, and allow for earlier diagnosis.

Rubinstein-Taybi syndrome: objective evaluation of craniofacial structure.

Rubinstein-Taybi syndrome (RTS) is a rare multiple congenital anomaly syndrome comprising mental and growth retardation, broad thumbs and great toes, and an unusual face. The classical facial appearance is well-established, striking and easy to recognize. It includes downslant of the palpebral fissures, epicanthic folds, ptosis, strabismus, highly arched palate, simple ears and a small mouth. The nose is distinctive with a beaked appearance, broad fleshy bridge, deviated septum and short low columella. Previous studies have documented considerable change in this facial phenotype with time. In this study, we evaluated 31 individuals with RTS from Great Britain and The Netherlands. They range in age from 1 to 39 years. Detailed craniofacial measurements were obtained on each subject and composite pattern profiles were compiled. There was remarkable concordance of patterns at all ages from infancy to adulthood. Microcephaly was present consistently. The head was relatively round with head width equal to head length. There was narrowness at the skull base with relative broadening of the minimal frontal diameter and lower facial width. The mouth was small and ears were broad and short. Eyes were wide-spaced in comparison to upper facial width and head circumference. The child under 4 years demonstrated some differences. Width and depth of the upper face exceeded that of the lower face, whereas with increasing age, mandibular dimensions were closer to normal than their maxillary counterparts. Despite these differences, the similarity of the profiles of all age groups seems to belie the phenotypic changes that can be appreciated subjectively. This suggests that major components of the change in appearance are those which have not been assessed in this study, such as palpebral fissure slant, deviation of the nasal bridge, presence of epicanthal folds or ptosis; or for which norms are not available, for example, beaking of the nose, and low nasal septum.

Follow-up study of patients with Wiedemann-Beckwith syndrome with emphasis on the change in facial appearance over time.

We have carried out a follow-up study of 13 children with Wiedemann-Beckwith syndrome (WBS) using a standard protocol which included facial anthropometric measurements. We confirm that most patients with WBS do well and that their clinical abnormalities become less apparent with age. We suggest that there is a characteristic neonatal appearance in WBS and that the expected pattern of facial growth generally results in a normal appearance by mid- to late childhood. We tentatively propose that there is a distinct facial anthropometric pattern profile in WBS.

Sotos syndrome: evolution of facial phenotype subjective and objective assessment.

Sotos syndrome is characterised by pre- and post-natal growth acceleration, advanced bone age, developmental delay and a typical facial Gestalt. We have evaluated 45 individuals with Sotos syndrome who were between age 1 and 25 years, in order to better define the change in facial appearance over time. In each individual, a thorough assessment was made, serial photographs were reviewed, and a series of anthropometric craniofacial measurements was obtained. These were compared with age- and sex-matched normal standards. Both clinical and anthropometric evaluations show that the facial appearance which most clinical geneticists would regard as "classical" is established early in life. The head is large and dolichocephalic, with a rounded and prominent forehead, accentuated by frontoparietal balding. There is narrowing at the temples, fullness of the cheeks, and tapering to a pointed chin. With time, the normal process of facial change occurs, superimposed on that typical Gestalt. As the face lengthens, the dominance of the forehead diminishes and the chin achieves greater prominence. The mandible is long and narrow inferiorly, square or pointed, but prognathism is rare. In a small proportion of patients, a rounder face early in life may challenge diagnosis, but follow-up of these large newborn and older infants should allow diagnosis by early childhood. Visualisation of pattern profiles at different ages, supplemented by statistical measures of variability and similarity, support the clinical impressions outlined above.

Congenital cholesteatoma and malformations of the facial nerve: rare manifestations of the BOR syndrome.

We describe a 14-month-old girl with unilateral congenital cholesteatoma and anomalies of the facial nerve in addition to the more common branchial arch, otic, and renal malformations comprising the branchio-oto-renal (BOR) syndrome. Her mother also has the BOR syndrome and unilateral duplication of the facial nerve. This is the first study of a BOR patient with congenital cholesteatoma and the second family in which cholesteatoma and anomalies of the facial nerve are described in patients with the BO/BOR syndrome. We review the congenital cholesteatoma literature and discuss hypotheses for the pathogenesis of this entity in light of this new report.

Renal tubular dysgenesis: a not uncommon autosomal recessive syndrome: a review.

Renal tubular dysgenesis is a recently recognized autosomal recessive condition characterized by short and poorly developed proximal convoluted tubules, leading to oligohydramnios, Potter sequence, and neonatal respiratory failure. We report an additional 9 cases from one pediatric center, suggesting that this syndrome is not as rare as was previously thought. Normal amniotic fluid volumes in affected pregnancies prior to the 22nd week of gestation have been documented, compromising early prenatal diagnosis. Late second trimester sonographic demonstration of oligohydramnios, with structurally normal kidneys, should suggest this diagnosis and the need for detailed post-mortem pathological examination.

Quantitative approach to identifying abnormal variation in the human face exemplified by a study of 278 individuals with five craniofacial syndromes.

We have two objectives in this study: to demonstrate the utility of two summary anthropometric measures for quantifying craniofacial variation and to explore some of their potential uses by physicians and clinical morphologists in general. The Craniofacial Variability Index (CVI) is a summary anthropometric measure of facial "harmony." The mean z-score, based on craniofacial anthropometry, is a measure of overall facial size. Both add an objective component to the assessment of individual facial variation and allow us to place the individual along a scale of continuous variation with predetermined limits of "normality" based on a reference or control series. Our results suggest that these summary measures coincide well with clinical assessments of abnormality in 278 individuals representing five distinct syndromes (Brachmann-de Lange, Prader-Willi, Rubinstein-Taybi, Smith-Magenis, and Sotos), each of which has an associated craniofacial component. Although craniofacial variation is continuous and the normal and syndromic populations overlap to varying degrees, the syndromic cases can be characterized in a variety of ways by using CVI as a measure of facial harmony and Mean-Z as an indicator of overall facial size. Thus, these two-objective measures offer a novel and efficient means of assessing craniofacial variation, whether they are used as tools in the clinical evaluation of subjects or as a means of exploring the nature of craniofacial variation within or between syndromes.

Noonan phenotype associated with neurofibromatosis.

We report on four patients with neurofibromatosis and manifestations of Noonan syndrome including short stature, ptosis, "midface hypoplasia," apparently short webbed neck, learning disabilities, and weakness. No family history of neurofibromatosis was present in any case. Average paternal and maternal age at birth was 37 and 28 years, respectively, suggestive of a new mutation. The presence of a distinct phenotype and hypotonia in these patients with neurofibromatosis is suggestive of a new separate disorder.

Possible new autosomal recessive syndrome with unusual renal histopathological changes.

We report a couple with repeated pregnancy loss--two spontaneous first trimester abortions and two stillbirths with diffuse hypoplasia of the renal tubules. Both parents have been investigated to exclude occult unilateral renal agenesis. We raise the possibility that this is a new autosomal recessive condition.

Deletion mapping of the beta-glucuronidase gene.

GUSB, the gene for beta-glucuronidase, has been localized to the proximal long arm of chromosome 7 between 7q11.2 and 7q22. Deficiency of beta-glucuronidase results in mucopolysaccharidosis type VII (MPS VII, Sly syndrome). The enzymatic defect has been demonstrated in cultured skin fibroblasts, leukocytes and serum of affected patients. An 8-yr-old boy presented with manifestations similar to MPS VII (mental retardation, short stature, "coarse" facial appearance, mild skeletal involvement and recurrent lower respiratory tract infection) but other, discrepant abnormalities, e.g., bilateral iris colobomata and cleft palate. Normal activity of beta-glucuronidase was found in the patient's leukocytes. Chromosome analysis disclosed an interstitial deletion of 7q with one breakpoint at the interface between bands 11.22 and 11.23 and the other breakpoint within band 21.1. DNA from this patient's leukocytes was analyzed for dosage of GUSB sequences. This locus appeared to be present at the normal diploid level. These findings suggest that GUSB is not in the portion of chromosome 7 deleted in our case, narrowing the smallest region of overlap to 7q21.1----7q22. We therefore assign the beta-glucuronidase gene to 7q21.1----7q22.

Noonan syndrome: the changing phenotype.

Among the multiple congenital anomalies (MCA) syndromes, the Noonan syndrome (NS) is a cardiofacial syndrome in which affected individuals may be short and mildly mentally retarded. Autosomal dominant inheritance of Noonan syndrome with variable expressivity has been documented in many families. Genetic heterogeneity has been postulated in Noonan syndrome because of the wide phenotypic variability, the relatively high incidence, and the occasional recurrence in sibs with apparently normal parents. Clinical variability is usual in autosomal dominant disorders, and mildly affected individuals may be difficult to recognize as gene carriers. Thus, a family with two or more affected children may simulate autosomal recessive inheritance. We have studied serial and family photographs of NS individuals in order to assess the likelihood of gene carriers' being missed in genetic studies. We have confirmed wide clinical variability within families, and more importantly, we have documented marked change of phenotype with age from the newborn period, infancy, childhood, and adolescence to adulthood. Manifestations in adults may be subtle and some without a known heart defect or other medically significant problems may have been considered normal in the past. Our study, while not ruling out causal heterogeneity, suggests that the change of phenotype with age may have been falsely perceived as clinical heterogeneity. A particular and subtle phenotype must be searched for in parents of affected children.

Anthropometric craniofacial pattern profiles in Down syndrome.

A series of 21 anthropometric craniofacial measurements was performed on 199 individuals with Down syndrome (DS), age 6 months to 61 years. These were compared to age and sex-matched normal standards, and Z score pattern profiles were constructed. These profiles confirmed brachycephaly and reduced ear length. With increasing age, maxillary growth was reduced in comparison to mandibular growth. Clinically, this was manifested by a change in facial shape from the characteristic round face of infancy to an oval shape in later life. Stepwise forward discriminant function analysis identified a subset of three variables (ear length, maxillary arc, and upper facial depth) which could accurately classify greater than 99% of the individuals in the combined sample of affected and unaffected individuals. Of the subjects with DS, 96.8% were classified correctly. These findings demonstrate the usefulness of anthropometric craniofacial pattern profiles in defining abnormal facial dimensions in particular syndromes and documenting the changes that occur with age. The technique should facilitate syndrome recognition, identification of carriers, and comparisons between syndromes.

Simpson-Golabi-Behmel syndrome associated with renal dysplasia and embryonal tumor: localization of the gene to Xqcen-q21.

We report 6 affected males in a 5-generation family with x-linked Simpson-Golabi-Behmel (SGB) syndrome. All had pre- and postnatal overgrowth with 2 adult males attaining heights over 195 cm. Other features included "coarse" face with hypertelorism, broad nasal root, cleft palate, full lips with a midline groove of the lower lip, grooved tongue with tongue tie, prominent mandible, congenital heart defects, arrhythmias, supernumerary nipples, splenomegaly, large dysplastic kidneys, cryptorchidism, hypospadias, skeletal abnormalities and postaxial hexadactyly. All affected individuals were of normal intelligence. One boy died at age 19 months of a neuroblastoma. The putative origin of the gene in this family was the maternal great grandmother of the propositus. Eight carrier females, who showed varying manifestations of the gene, have been identified. Anthropometric analysis has identified preliminary characteristic craniofacial dimensions in this syndrome. Molecular studies have shown a maximal lod score of 2.81 with no recombinants observed for the SGB-DXYS68 pairing, mapping the disorder to Xqcen-Xq21.3.

Cytogenetic findings in 318 couples with repeated spontaneous abortion: a review of experience in British Columbia.

We studied G-banded chromosome complements on 318 couples with 2 or more spontaneous abortions. Seven chromosome abnormalities were detected. Three women and one man were identified as carriers of balanced Robertsonian translocations, t(13;14), t(13;14), t(13;21), and t(14;22), respectively. Aneuploidy: 47,XXX; 47,XX, + marker; and 45,X/46,XX/47,XXX were found in the other 3 women. The overall aberration frequency was 2.2% of couples. When a stringent criterion of greater than or equal to 3 consecutive spontaneous abortions was used, the frequency was 4.2%. In this series no chromosome aberrations were identified in couples with 2 spontaneous abortions and a live-born child with congenital anomalies; 1 of 22 couples with 2 spontaneous abortions and a still-born infant showed a chromosomal abnormality. Findings from the recent literature are compared with those from this study.