Clinical variability within Brachmann-de Lange syndrome: A proposed classification system

Seven patients, including two sibs, with the Brachmann-de Lange syndrome (BDLS) are presented as representative of the different types of BDLS in a proposed classification system. Type I (“classic”) patients have the characteristic facial and skeletal changes of BDLS using the criteria in the diagnostic index of Preus and Rex. Type I is distinguished from the other subtypes by prenatal growth deficiency (< 2.5 S.D. below mean for gestation) becoming more severe postnatally (< 3.5 S.D. below the mean), moderate to profound psychomotor retardation, and major malformations which result in severe disability or death. Type II (“mild”) BDLS patients have similar facial and minor skeletal abnormalities to those seen in type I; however, these changes may develop with time or may be partially expressed. Patients with type II BDLS are distinguished from those with other types by mild to borderline psychomotor retardation, less severe pre-and postnatal growth deficiency, and the absence of (or loss severe) major malformations. Behavioral problems can be a significant clinical problem in type II BDLS. Type III (“phenocopies”) BDLS includes patients who have phenotypic manifestations of BDLS which are causally related to chromosomal aneuploidies or teratogenic exposures. © 1993 Wiley-Liss, Inc.     

Chromatinopathies: A focus on Cornelia de Lange syndrome

In recent years, many genes have been associated with chromatinopathies classified as “Cornelia de Lange Syndrome-like.” It is known that the phenotype of these patients becomes less recognizable, overlapping to features characteristic of other syndromes caused by genetic variants affecting different regulators of chromatin structure and function. Therefore, Cornelia de Lange syndrome diagnosis might be arduous due to the seldom discordance between unexpected molecular diagnosis and clinical evaluation. Here, we review the molecular features of Cornelia de Lange syndrome, supporting the hypothesis that “CdLS-like syndromes” are part of a larger “rare disease family” sharing multiple clinical features and common disrupted molecular pathways.     

Mild Brachmann-de Lange syndrome. Phenotypic and developmental characteristics of mildly affected individuals

Since 1981, we have identified 3 patients with mild Brachmann-de Lange syndrome (BDLS) who have had subtle but definite manifestations of the syndrome and mild effects on growth and development. J.G. (B.D. 12/9/72) was first examined at 20 months. He had rather typical craniofacial findings and hirsutism, limitation of full supination of his arms, and brachyclinodactyly of the 5th fingers. IQ was estimated at 65. K.H. (B.D. 10/10/83) was first examined by us at age 9 months and was diagnosed as having “mild” BDLS. At age 5, K.H. has demonstrated relatively normal cognitive development (low average–average IQ of 74) with specific learning problems: weakness of visual-motor skills, delayed expressive language development, and articulation difficulties. At age 7, he was attending a regular 1st grade classroom, with some special education assistance. M.E.(B.D. 4/19/78) was diagnosed at age 10 years as having “mild” BDLS. His physical changes were more subtle than those of the 2 patients above. At age 10, M.E. was in the regular 4th grade classroom receiving special education support. His IQ was in the borderline-low-average range. He had strengths in rote verbal skills, with weaknesses in reading and writing. These 3 patients demonstrate mild BDLS in which characteristic manifestations of the syndrome, particularly craniofacial anomalies, are present and recognizable, but quite subtle, thus making the clinical diagnosis difficult. In addition, the milder physical phenotype is associated with milder cognitive and behavioral consequences. When comparing patients with mild BDLS to those in our practice (4 others) with typical changes, we find that birth weight, absence of major anomalies, and subtlety of craniofacial abnormalities are predictive of mildly affected patients. © 1993 Wiley-Liss, Inc.     

Definition and diagnosis of the Brachmann–De Lange syndrome

We have classified patients referred for suspicion of the Brachmann–De Lange syndrome (BDLS) into two groups using techniques of numerical taxonomy. Patients with the syndrome share an array of abnormal characteristics, and those without it have different abnormal characteristics. A group of 30 characters that best distinguish the two groups of patients was used to construct a diagnostic index. The index score is expected to divide 99% of patients into those with and without the syndrome, leaving 1% in a “zone of doubt.” All 46 patients used to construct the index and 16 new patients had scores in either the BDLS or non-BDLS range and none were in the zone of doubt. A previously published index using metacarpal-phalangeal measurements, although less discriminatory, confirmed our findings in 84% of 25 patients tested, the remainder having scores in the zone of doubt for that index.     

Mild mental retardation with classic somatic phenotype in the Brachmann-de Lange syndrome

Severe Mental retardation is the most handicapping disability for individuals with Brachmann-de Lange syndrome (BDLS). Reports of higher functioning patients with suspected BDLS have invariably described those with a “mild” BDLS somatic phenotype. Here we report on 2 high-functioning females, ages 3.7 and 10.6 years, with the classic BDLS somatic phenotype, i.e., all growth parameters at 4–5 standard deviations bellow the mean prenatally and postnatally. These 2 patients serve to extend the spectrum of classic BDLS to include cognitive function in the mild-to -moderate range of mental retardation. © 1993 Wiley-Liss, Inc.     

Genomic analysis of “microphenotypes” in epilepsy

Large international consortia examining the genomic architecture of the epilepsies focus on large diagnostic subgroupings such as “all focal epilepsy” and “all genetic generalized epilepsy”. In addition, phenotypic data are generally entered into these large discovery databases in a unidirectional manner at one point in time only. However, there are many smaller phenotypic subgroupings in epilepsy, many of which may have unique genomic risk factors. Such a subgrouping or “microphenotype” may be defined as an uncommon or rare phenotype that is well recognized by epileptologists and the epilepsy community, and which may or may not be formally recognized within the International League Against Epilepsy classification system. Here we examine the genetic structure of a number of such microphenotypes and report in particular on two interesting clinical phenotypes, Jeavons syndrome and pediatric status epilepticus. Although no single gene reached exome-wide statistical significance to be associated with any of the diagnostic categories, we observe enrichment of rare damaging variants in established epilepsy genes among Landau–Kleffner patients (GRIN2A) and pediatric status epilepticus patients (MECP2, SCN1A, SCN2A, SCN8A).     

Brachmann-de Lange syndrome. Delineation of the clinical phenotype

A total of 31 cases previously diagnosed as having Brachmann-de Lange syndrome were ascertained and examined, of which 11 were thought to have been misdiagnosed. Of those correctly diagnosed, there appeared to be a phenotypic dichotomy with classical and mild cases. Those facial findings of greatest diagnostic value were the combination of the characteristic eyebrows, long philtrum, thin lips and crescent-shaped mouth. The characteristic eyebrows were neat, well defined and arched as though they had been pencilled. This combination of anomalies was absent in postpubertal males but not in postpubertal females. Facial abnormalities most likely to lead to incorrect use of the eponym were hypertrichosis, synophrys, and bushy eyebrows. © 1993 Wiley-Liss, Inc.     

Physical growth in Brachmann-de Lange syndrome

Growth in 30 patients with Brachmann-de Lange syndrome (BDLS) was evaluated and found to be deficient in 27/30, with 17/27 having intrauterine growth retardation (IUGR). In 12/27 Patients, endocrine evaluations have been completed. Seven of 12 were normal and 4/12, one with empty sella, had “classical” growth hormone deficiency with extreme short stature, markedly delayed skeletal maturation and subnormal growth hormone secretion in response to provocative stimuli. One of 12 patients had discordance between insulin growth factor I levels and growth hormone responses to insulin and clonidine suggestive of end organ resistance to growth harmone. It appears that the hypothalmamic-pituitary function is compromised in at least some BDLS patients. Thus, endocrine evaluations are warranted for the patients with short stature. © 1993 Wiley-Liss, Inc.     

Bloom syndrome does not always present with sun-sensitive facial erythema

Bloom syndrome is an autosomal recessive condition characterized by severe pre- and postnatal growth deficiency, immunodeficiency, an increased risk for malignancies, craniofacial dysmorphisms, and “typical” erythematous sun-sensitive skin lesions of the face. This facial rash has a butterfly-shaped distribution around the nose and is usually observed for the first time during the early years of life. Though reported as being a main feature of Bloom syndrome, there seems to be phenotypic variability regarding this facial skin rash among patients. It has been previously reported that in some individuals with Bloom syndrome these sun-sensitive lesions are less prominent or even absent. In this report we describe a 36 year old woman with short stature, microcephaly, several dysmorphisms, congenital hypothyroidism and premature ovarian failure. She was diagnosed with nasopharyngeal carcinoma at 36 years of age, only a few months after her consultation at the department of Clinical Genetics. Whole Exome Sequencing demonstrated that she had Bloom syndrome caused by a compound heterozygous mutation in BLM (c.2207_2212delinsTAGATTC; p.(Tyr736Leufs*5) and c.3681del; p.(Lys1227Asnfs*52)). She did not have facial sun-sensitive erythematous rash during childhood nor adulthood. We conclude that Bloom syndrome does not always present with erythematous sun-sensitive skin lesions of the face. We would like to underline that phenotypic variation regarding this “hallmark” feature of Bloom syndrome exists. Being aware of this might prevent a delay in diagnosing this rare short-stature syndrome and, subsequently, its potential clinical implications.     

Summary of the 1993 ASHG ancillary meeting “recent research on chromosome 4p syndromes and genes”

The following is a summary of presentations given during an ancillary meeting to the 1993 American Society of Human Genetics Meeting in New Orleans, LA. This ancillary meeting, entitled “Recent Research on Chromosome 4p Syndromes and Genes,” reviewed the history of the Wolf-Hirschhorn syndrome (WHS), the natural history of patients with WHS, and the smallest region of deletion associated with the WHS. The proximal 4p deletion syndrome and the duplication 4p syndrome were also described and advice was offered regarding detection of chromosome 4p deletions, duplications, and rearrangements. The current status of the physical map of chromosome 4p with emphasis on the genes that map to the 4p16 region was presented along with a preliminary phenotypic map of 4p16. The goal of this format was to provide a comprehensive review of the clinical presentations, diagnostic capabilities, and genetic mapping advances involving chromosome 4p. © 1995 Wiley-Liss, Inc.     

de Lange syndrome: A clinical review of 310 individuals

Three hundred ten individuals with a clinical diagnosis of de Lange syndrome were seen and examined in conjunction with the parent support group. One hundred thirty-four males and 176 females whose ages ranged from birth to 37 years made up the study group. Examination findings were recorded for those features described by de Lange in her original report of the syndrome to determine the frequency and significance of each. In addition, questionnaires were completed by 128 of these families and medical, growth and developmental records were collected. The clinical diagnosis seems best supported by the facial features of the syndrome including the long eyelashes and confluent eyebrows (synophrys), although additional characteristics are needed. Only 27% had the upper limb deficiencies commonly associated with the syndrome. Growth was retarded in nearly all individuals, often of prenatal onset. Medical problems occurred frequently and most often involved the eye and ear, as well as the cardiac and gastrointestinal systems. Of 14 deaths, almost half were secondary to cardiac or gastrointestinal complications. The recurrence risk in 377 sibs of the patients was calculated to be less than 1%. Although development lagged significantly in speech, most individuals developed good self-help skills. The study demonstrated a higher proportion of patients affected mildly with the syndrome than is commonly appreciated. This underscores the importance of early recognition and appropriate medical and developmental support. © 1993 Wiley-Liss, Inc.     

A comprehensive scoring system for evaluating noonan syndrome

A multidisciplinary team assessed 23 patients with various manifestations of the Noonan syndrome, including pulmonary valve stenosis (with leaflet dysplasia), “typical” facial appearance (including hypertelorism, epicanthic folds, flat nasal bridge, and apparently low-set ears), short stature, and mental retardation. Seven patients had a family history of the syndrome. A comprehensive scoring system was devised on the basis of frequency and severity of manifestations and results of invasive and noninvasive tests in these patients and those reported in the literature. The scoring system was condensed into a score card for clinical use and validated by “blind” application to patients with isolated pulmonary valve stenosis or suspected Noonan syndrome. Use of a scoring system to diagnose a syndrome for which there is no specific diagnostic test facilitates accuracy and decreases observer bias. In the case of unusual congenital disorders it is particularly valuable for a pediatrician in general practice.     

Mild “duplication 6q syndrome”: A case with partial trisomy (6)(q23.3q25.3)

We report on a female infant with partial 6q trisomy (46,XX,dir dup(6)(q23.3q25.3)) and phenotypic characteristics of the “duplication 6q syndrome,” including intrauterine growth retardation, dolichocephaly, depressed nasal bridge, almond-shaped palpebral fissures, short neck, flexion-contractures of the wrists, and mild generalized hypertonia. Although clearly belonging to the described “duplication 6q syndrome,” her features were milder than those found in the literature. Comparison of the phenotype of this child with other published reports indicates that specific phenotypic components of the duplication 6q syndrome cannot be attributed to duplication of a specific band or bands on 6q. Am. J. Med. Genet. 68:450–454, 1997. © 1997 Wiley-Liss, Inc.     

Barakat syndrome revisited

Barakat syndrome also known as HDR syndrome (Online Mendelian Inheritance in Man [OMIM] 146255), was first described by Barakat et al. in 1977 . It is a rare genetic disorder characterized by the triad of hypoparathyroidism “H,” sensorineural deafness “D,” and renal disease “R.” The defect is caused by deletions in chromosome 10p14 or mutations in the GATA3 gene. Although the syndrome has been phenotypically defined by this triad the literature identifies cases with different components with, or without GATA3 defects making the definition of the syndrome confusing. We analyzed 180 cases and attempted to define the phenotype of the syndrome and suggest guidelines for diagnosis. We suggest that the diagnosis could be confirmed in patients who have all three components, and in those who have two components with a positive family history. GATA3 testing is optional to establish the diagnosis in these patients. The syndrome should be considered in patients with isolated “D” where other causes of “D” have been excluded and those with isolated “R,” especially if there is family history of any of these components. In these instances, confirmatory GATA3 testing is indicated to confirm the diagnosis. In patients with nonsurgical “H,” where “D” and “R” have been conclusively ruled out GATA3 studies are not needed as none of these patients were shown to be GATA3 haploinsufficient. Only 64.4% of patients in our review had “HDR.” Some findings might have not been recognized or may could have appeared later in life, but it is evident that this syndrome is genotypically heterogeneous.     

Prometaphase chromosomes in five patients with the Brachmann-de Lange syndrome

We analyzed the prometaphase chromosomes of 5 patients (including one pair of sibs) with the Brachmann-de Lange syndrome (BDLS), and did not find a significant chromosome abnormality in any of them. It appears that two distinct entities can be distinguished on clinical and chromosomal bases: the BDLS and the dup(3q) syndrome. We still recommend chromosome studies in any patients with BDLS and BDLS-like manifestations.     

Coloboma,mental retardation,hypogonadism, and obesity: Critical review of the so-called Biemond syndrome type 2, updated nosology,and delineation of three “new” syndromes

Biemond syndrome type 2 (BS2) is classically regarded as a recessively inherited condition (MIM 210350) comprising mental retardation, coloboma, obesity, polydactyly, hypogonadism, hydrocephalus, and facial dysostosis. Clinically, the disorder is closely related to Bardet-Biedl syndrome. Few cases have been reported, most of them before 1970. We present clinical data on three mentally retarded sporadic cases with coloboma, obesity, and hypogenitalism (in two of them), fitting at first glance a diagnosis of BS2. A review documents striking clinical variability among the patients said to have BS2. We propose a new nosology of those cases and delineate several new clinical forms. Purported BS2 cases may be divided into: (1) Bardet-Biedl syndrome with fortuitous coloboma or aniridia, (2) BS2 sensu stricto, a recessively inherited syndrome of sexual infantilism, short stature, coloboma, and preaxial polydactyly without obesity, only known from the original report, (3) a “new” dominantly inherited form of colobomatous microphthalmia occasionally associated with obesity, hypogonadism, and mental retardation, to which our observations belong, (4) cytogenetically proven Rubinstein-Taybi syndrome (one case), (5) an unclassifiable, early lethal familial syndrome resembling Buntinx-Majewski syndrome, and (6) a “new” coloboma-zygodactyly-clefting syndrome. The latter two syndromes may result from chromosomal anomaly. Am. J. Med. Genet. 69:370–379, 1997. © 1997 Wiley-Liss, Inc.     

Variability of the Brachmann-de Lange Syndrome

Brachmann-de Lange syndrome (BDLS) is a relatively common multiple congenital anomaly/mental retardation syndrome, whose cause is unknown. The clinical variability of this condition is well-known. Recently some reports suggested the possible existence of a mild BDLS phenotype. We report on 30 patients in whom a diagnosis of BDLS was made or strongly suspected in 12 different Italian hospitals. Based on clinical evaluation we divided them into two groups, classical and mild BDLS cases. We compare the clinical data of these patients and we discuss the problems which arise in trying to define clear criteria of distinction between these two groups. © 1993 Wiley-Liss, Inc.     

The trisomy 4p syndrome: Case report and review

We report a further case of trisomy 4p: a 5-year-old mentally retarded boy with characteristic facial features, eye abnormalities, flexion contractures, several bone anomalies, and hyperactivity. In a review of 27 cases (11♂, 16♀, 22 families) the cytogenetic and clinical data were tabulated and analyzed. Diagnosis is established by karyotype: there is always partial or apparently “total” trisomy of the short arm of chromosome 4. In 19 families a parent carried either a balanced translocation (16 times) or a pericentric inversion (3 times); 3 patients had de novo duplication of 4p. In several cases, additional deletions or trisomies were present. From the analysis of all cases, but particularly of the “pure” trisomies, the phenotypic spectrum of this condition was observed and found to be a specific multiple congenital anomaly/mental retardation (MCA/MR) syndrome. Its main features are a characteristic facial appearance, postnatal growth retardation, severe psychomotor retardation with or without seizures, microcephaly, and various major and minor anomalies.     

Partial duplication of 3q (q25.1→q26.1) without the Brachmann-de Lange phenotype

Partial duplications of chromosome 3 have previously been reported to have phenotypic characteristics similar to Brachmann-de Lange syndrome (BDLS). We present the case of a 13-Year-old girl with an apparent duplication in the 3q25.1→q26.1 region but none of the manifestations commonly seen in BDLS. The chromosome 3 duplication was confirmed with a FISH painting probe of the involved region. These results suggest that the region critical for Brachmann-de Lange syndrome is not within the duplicated region of 3q25.1→q26.1. © 1993 Wiley-Liss, Inc.     

Brachmann-de Lange syndrome: Diagnostic difficulties posed by the mild phenotype

We described 4 patients with facial changes of Brachmann-de Lange syndrome but without limb defects. Mental retardation ranged from moderate to severe and the degree of Prenatal and postnatal growth deficiency was variable. These patients exemplify the diagnostic difficulties and counseling dilemmas posed by the mild Brachmann-de Lange phenotype. The relationship of the mild phenotype to the full syndrome will not be understood until the pathogenetic or causal factor(s) are delineated. © 1993 Wiley-Liss, Inc.