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Protein translation is an essential cellular process and dysfunctional protein translation causes various neurodevelopmental disorders. The eukaryotic translation elongation factor 1A (eEF1A) delivers aminoacyl-tRNA to the ribosome, while the eEF1B complex acts as a guanine exchange factor (GEF) of GTP for GDP indirectly catalyzing the release of eEF1A from the ribosome. The gene EEF1D encodes the eEF1Bδ subunit of the eEF1B complex. EEF1D is alternatively spliced giving rise to one long and three short isoforms. Two different homozygous, truncating variants in EEF1D had been associated with severe intellectual disability and microcephaly in two families. The published variants only affect the long isoform of EEF1D that acts as a transcription factor of heat shock element proteins. By exome sequencing, we identified two different homozygous variants in EEF1D in two families with severe developmental delay, severe microcephaly, spasticity, and failure to thrive with optic atrophy, poor feeding, and recurrent aspiration pneumonias. The EEF1D variants of this study are localized in the C-terminal GEF domain suggesting that a disturbed protein translation machinery might contribute to the neurodevelopmental phenotype. Pathogenic variants localized in both the alternatively spliced domain or in the GEF domain of EEF1D cause a severe neurodevelopmental disorder with microcephaly and spasticity. This article is protected by copyright. All rights reserved.

Both point mutations and deletions of the MYT1L gene as well as microdeletions of chromosome band 2p25.3 including MYT1L are associated with intellectual disability, obesity, and behavioral problems. Thus, MYT1L is assumed to be the-at least mainly-causative gene in the 2p25.3 deletion syndrome. Here, we present comprehensive descriptions of nine novel individuals bearing MYT1L mutations; most of them single nucleotide variants (SNVs). This increases the number of known individuals with causative deletions or SNVs of MYT1L to 51. Since eight of the nine novel patients bear mutations affecting MYT1L only, the total number of such individuals now nearly equals the number of individuals with larger microdeletions affecting additional genes, allowing for a comprehensive phenotypic comparison of these two patient groups. For example, 55% of the individuals with mutations affecting MYT1L only were overweight or obese as compared to 86% of the individuals with larger microdeletions. A similar trend was observed regarding short stature with 5 versus 35%, respectively. However, these differences were nominally significant only after correction for multiple testing, further supporting the hypothesis that MYT1L haploinsufficiency is central to the 2p25.3 deletion phenotype. Most importantly, the large number of individuals with MYT1L mutations presented and reviewed here allowed for the delineation of a more comprehensive clinical picture. Seizures, postnatal short stature, macrocephaly, and microcephaly could be shown to be over-represented among individuals with MYT1L mutations.

Limitations in genetic stability and recapitulating accurate physiological disease properties challenge the utility of patient-derived (PD) cancer models for reproducible and translational research. A portfolio of isogenic human induced pluripotent stem cells (hiPSCs) with different pan-cancer relevant oncoprotein signatures followed by differentiation into lineage-committed progenitor cells was genetically engineered. Characterization on molecular and biological level validated successful stable genetic alterations in pluripotency state as well as upon differentiation to prove the functionality of our approach. Meanwhile proposing core molecular networks possibly involved in early dysregulation of stem cell homeostasis, the application of our cell systems in comparative substance testing indicates the potential for cancer research such as identification of augmented therapy resistance of stem cells in response to activation of distinct oncogenic signatures.

Holoprosencephaly (HPE) has been defined as a distinct clinical entity with characteristic facial gestalt, which may-or may not-be associated with the true brain malformation observed post-mortem in autopsy or in pre- or postnatal imaging. Affected families mainly show autosomal dominant inheritance with markedly reduced penetrance and extremely broad clinical variability even between mutation carriers within the same families. We here present advances in prenatal imaging over the last years, increasing the proportion of individuals with HPE identified prenatally including milder HPE forms and more frequently allowing to detect more severe forms already in early gestation. We report the results of diagnostic genetic testing of 344 unrelated patients for HPE at our lab in Germany since the year 2000, which currently with the application of next generation sequencing (NGS) panel sequencing identifies causal mutations for about 31% (12/38) of unrelated individuals with normal chromosomes when compared to about 15% (46/306) using conventional Sanger sequencing and Multiplex Ligation-dependent Probe Amplification (MLPA). More comprehensive genetic testing by our in house NGS panel sequencing of 10 HPE associated genes (MiSeq (TM) and NextSeq (TM) 500, Illumina, Inc., San Diego, CA) not only allowed to include genes with smaller contribution to the phenotype, but may also unravel additional low frequency or more common genetic variants potentially contributing to the observed large intrafamiliar variability and may ultimately guide our understanding of the individual clinical manifestation of this complex developmental disorder.

Introduction Heterozygous BICD2 gene mutations cause a form of autosomal dominant spinal muscular atrophy with lower extremity predominance (SMALED). Methods We analyzed the BICD2 gene in a selected group of 25 index patients with neurogenic muscle atrophy. Results We identified 2 new BICD2 missense mutations, c.2515G>A, p.Gly839Arg, in a family with autosomal dominant inheritance, and c.2202G>T, p.Lys734Asn, as a de novo mutation in an isolated patient with similar phenotype. The patients had congenital foot contractures, muscle atrophy of the legs, and slowly progressive weakness of the shoulder girdle. There was no apparent sensory or brain dysfunction. One patient died of unrelated reasons at age 52 years. Autopsy revealed no upper motor neuron and only moderate lower motor neuron loss, but there was distal corticospinal tract degeneration and marked neurogenic muscular atrophy. Conclusion These findings give further insight into the clinical and pathoanatomical consequences of BICD2 mutations. Muscle Nerve 54: 496–500, 2016

Cornelia de Lange syndrome (CdLS) is a clinically heterogeneous disorder characterized by typical facial dysmorphism, cognitive impairment and multiple congenital anomalies. Approximately 75% of patients carry a variant in one of the five cohesin-related genes NIPBL, SMC1A, SMC3, RAD21 and HDAC8. Herein we report on the clinical and molecular characterization of 11 patients carrying 10 distinct variants in HDAC8. Given the high number of variants identified so far, we advise sequencing of HDAC8 as an indispensable part of the routine molecular diagnostic for patients with CdLS or CdLS-overlapping features. The phenotype of our patients is very broad, whereas males tend to be more severely affected than females, who instead often present with less canonical CdLS features. The extensive clinical variability observed in the heterozygous females might be at least partially associated with a completely skewed X-inactivation, observed in seven out of eight female patients. Our cohort also includes two affected siblings whose unaffected mother was found to be mosaic for the causative mutation inherited to both affected children. This further supports the urgent need for an integration of highly sensitive sequencing technology to allow an appropriate molecular diagnostic, genetic counseling and risk prediction.

Using whole-exome sequencing, we identified a homozygous acceptor splice-site mutation in intron 6 of the KATNB1 gene in a patient from a consanguineous Turkish family who presented with congenital microcephaly, lissencephaly, short stature, polysyndactyly, and dental abnormalities. cDNA analysis revealed complete loss of the natural acceptor splice-site resulting either in the usage of an alternative, exonic acceptor splice-site inducing a frame-shift and premature protein truncation or, to a minor extent, in complete skipping of exon 7. Both effects most likely lead to complete loss of KATNB1 function. Homozygous and compound heterozygous mutations in KATNB1 have very recently been described as a cause of microcephaly with brain malformations and seizures. We extend the KATNB1 associated phenotype by describing a syndrome characterized by primordial dwarfism, lissencephaly, polysyndactyly, and dental anomalies, which is caused by a homozygous truncating KATNB1 mutation.

The clinical diagnosis of Lujan-Fryns syndrome (LFS) comprises X-linked intellectual disability (XLID) with marfanoid habitus, distinct combination of minor facial anomalies and nasal speech. However the definition of syndrome was significantly broadened since the original report and implies ID with marfanoid habitus. Mutations of three genes (MED12, UPF3B, and ZDHHC9) have been reported in "broadly defined" LFS. We examined these genes in 28 individuals with a tentative clinical diagnosis of LFS but we did not identify any causative mutation. By molecular karyotyping we detected other disorders, i.e., Phelan-McDermid syndrome and 16p11.2 microduplication, each in one patient. One affected individual was carrier of a different recurrent duplication on 16p11.2 that has been reported several times to the DECIPHER and ISCA databases in individuals with autism, intellectual disability (ID), and developmental delay. It may represent a new duplication syndrome. We also identified previously unreported de novo duplication on chromosome 12p13.31 which we considered to be disease-causing. X-exome sequencing of four individuals revealed private or non-recurrent mutations in NKAP and LAS1L in one patient each. While LFS is defined as a form of XLID, there seem to be various conditions that have rather similar phenotypes. Therefore, the combination of ID and marfanoid habitus in a male patient is not sufficient for the diagnosis of LFS. We suggest that the diagnosis of LFS in patients with ID and marfanoid habitus should be made only in presence of specific facial features, nasal speech and obvious X-linked segregation of the disorder or an unambiguously pathogenic mutation in the MED12. (c) 2015 Wiley Periodicals, Inc.

We present clinical features and genetic results of 1206 index patients and 124 affected relatives who were referred for genetic testing of Charcot-Marie-Tooth (CMT) neuropathy at the laboratory in Aachen between 2001 and 2012. Genetic detection rates were 56% in demyelinating CMT (71% of autosomal dominant (AD) CMT1/CMTX), and 17% in axonal CMT (24% of AD CMT2/CMTX). Three genetic defects (PMP22 duplication/deletion, GJB1/Cx32 or MPZ/P0 mutation) were responsible for 89.3% of demyelinating CMT index patients in whom a genetic diagnosis was achieved, and the diagnostic yield of the three main genetic defects in axonal CMT (GJB1/Cx32, MFN2, MPZ/P0 mutations) was 84.2%. De novo mutations were detected in 1.3% of PMP22 duplication, 25% of MPZ/P0, and none in GJB1/Cx32. Motor nerve conduction velocity was uniformly 40 m/s in MFN2, and more variable in GJB1/Cx32, MPZ/P0 mutations. Patients with CMT2A showed a broad clinical severity regardless of the type or position of the MFN2 mutation. Out of 75 patients, 8 patients (11%) with PMP22 deletions were categorized as CMT1 or CMT2. Diagnostic algorithms are still useful for cost-efficient mutation detection and for the interpretation of large-scale genetic data made available by next generation sequencing strategies.

DOORS syndrome (Deafness, Onychodystrophy, Osteodystrophy, mental Retardation, Seizures) is characterized mainly by sensorineural deafness, shortened terminal phalanges with small nails of hands and feet, intellectual deficiency, and seizures. Half of the patients with all clinical features have mutations in TBC1D24. We review here the manifestations of patients clinically diagnosed with DOORS syndrome. In this cohort of 32 families (36 patients) we detected 13 individuals from 10 families with TBC1D24 mutations. Subsequent whole exome sequencing in the cohort showed the same de novoSMARCB1 mutation (c.1130G>A), known to cause Coffin-Siris syndrome, in two patients. Distinguishing features include retinal anomalies, Dandy-Walker malformation, scoliosis, rocker bottom feet, respiratory difficulties and absence of seizures, and 2-oxoglutaric aciduria in the patients with the SMARCB1 mutation. We briefly discuss the heterogeneity of the DOORS syndrome phenotype and the differential diagnosis of this condition.

Evidence is now accumulating from a number of sequencing studies that ARID1B not only appears to be one of the most frequently mutated intellectual disability (ID) genes, but that the range of phenotypes caused by ARID1B mutations seems to be extremely wide. Thus, it is one of the most interesting ID genes identified so far in the exome sequencing era. In this article, we review the literature surrounding ARID1B and attempt to delineate the ARID1B phenotype. The vast majority of published ARID1B patients have been ascertained through studies of Coffin-Siris syndrome (CSS), which leads to bias when documenting the frequencies of phenotypic features. Additional observations of those individuals ascertained through exome sequencing studies helps in delineation of the broader clinical phenotype. We are currently establishing an ARID1B consortium, aimed at collecting ARID1B patients identified through genome-wide sequencing strategies. We hope that this endeavor will eventually lead to a more comprehensive view of the ARID1B phenotype.

Nicolaides-Baraitser syndrome (NCBRS) is an intellectual disability (ID)/multiple congenital anomalies syndrome caused by non-truncating mutations in the ATPase region of SMARCA2, which codes for one of the two alternative catalytic subunits of the BAF chromatin remodeling complex. We analyzed 61 molecularly confirmed cases, including all previously reported patients (n = 47) and 14 additional unpublished individuals. NCBRS is clinically and genetically homogeneous. The cardinal features (ID, short stature, microcephaly, typical face, sparse hair, brachydactyly, prominent interphalangeal joints, behavioral problems and seizures), are almost universally present. There is variability however, as ID can range from severe to mild, and sparse hair may be present only in certain age groups. There may be a correlation between the severity of the ID and presence of seizures, absent speech, short stature and microcephaly. SMARCA2 mutations causing NCBRS are likely to act through a dominant-negative effect. There may be some genotype-phenotype correlations (mutations at domain VI with severe ID and seizures; mutations affecting residues Pro883, Leu946, and Ala1201 with mild phenotypes) but numbers are still too small to draw definitive conclusions.

Coffin-Siris syndrome (CSS) is a rare congenital malformation syndrome, recently found to be caused by mutations in several genes encoding components of the BAF complex. To date, 109 patients have been reported with their mutations: SMARCB1 (12%), SMARCA4 (11%), SMARCE1 (2%), ARID1A (7%), ARID1B (65%), and PHF6 (2%). We review genotype-phenotype correlation of all previously reported patients with mutations in SMARCB1, SMARCA4, SMARCE1, and ARID1A through reassessment of their clinical and molecular findings. Cardinal features of CSS included variable degrees of intellectual disability (ID) predominantly affecting speech, sucking/feeding difficulty, and craniofacial (thick eyebrows, long eyelashes), digital (hypoplastic 5th fingers or toes, hypoplastic 5th fingernails or toenails), and other characteristics (hypertrichosis). In addition, patients with SMARCB1 mutations had severe neurodevelopmental deficits including severe ID, seizures, CNS structural abnormalities, and no expressive words as well as scoliosis. Especially, those with a recurrent mutation "p.Lys364del" represented strikingly similar phenotypes including characteristic facial coarseness. Patients with SMARCA4 mutations had less coarse craniofacial appearances and behavioral abnormalities. Patients with SMARCE1 mutations had a wide spectrum of manifestations from severe to moderate ID. Patients with ARID1A also had a wide spectrum of manifestations from severe ID and serous internal complications that could result in early death to mild ID. Mutations in SMARCB1, SMARCA4, and SMARCE1 are expected to exert dominant-negative or gain-of-function effects, whereas those in ARID1A are expected to exert loss-of-function effects.

Recently, de novo aberrations in PHF6 were identified in females with intellectual disability and with a distinct phenotype including a characteristic facial gestalt with bitemporal narrowing, prominent supraorbital ridges, synophrys, a short nose and dental anomalies, tapering fingers with brachytelephalangy, clinodactyly and hypoplastic nails, short toes with hypoplastic nails, and linear skin hyperpigmentation. In adolescent or older patients, this phenotype overlaps but is not identical with Borjeson-Forssman-Lehmann syndrome in males, caused by X-linked recessive mutations in PHF6. In younger girls there seems to be a striking phenotypic overlap with Coffin-Siris syndrome, which is characterized by intellectual disability, sparse hair and hypoplastic nails. This review will summarize and characterize the female phenotype caused by de novo aberrations in PHF6 and will discuss the overlapping and distinguishing features with Coffin-Siris syndrome.

The human facial dysostoses can be subdivided into mandibulofacial dysostoses (MFDs) and acrofacial dysostoses (AFDs). The craniofacial phenotypes of the two groups of patients are similar. Both types are thought to be related to abnormal migration of neural crest cells to the pharyngeal arches and the face. The craniofacial anomalies shared by the two groups consist of downslanting palpebral fissures, coloboma of the lower eyelid, from which the eyelashes medial to the defect may be absent, hypoplasia of the zygomatic complex, micrognathia, and microtia, which is often associated with hearing loss. These facial deformities are associated with limb anomalies in the AFDs. All MFDs present with the typical craniofacial phenotype, but some have additional features that help to distinguish them clinically: intellectual disability, microcephaly, chest deformity, ptosis, cleft lip/palate, macroblepharon, or blepharophimosis. The limb anomalies in the AFDs can be classified into pre-axial, post-axial, and others not fitting into the first two AFD types. Of the pre-axial types, Nager syndrome and of the post-axial types, Miller syndrome are the best-known disorders of their AFD subgroups. Several other AFDs with unknown molecular genetic bases, including lethal ones, have been described. This article reviews the MFDs and AFDs published to date.

High-resolution microarray technology has facilitated the detection of submicroscopic chromosome aberrations and characterization of new microdeletion syndromes. We present clinical and molecular data of five patients with previously undescribed overlapping interstitial deletions involving 8q22.2q22.3. All deletions differ in size and breakpoints. Patients 1-4 carry deletions between 5.25 and 6.44 Mb in size, resulting in a minimal deletion overlap of 3.87 Mb (from 100.69 to 104.56 Mb; hg18) comprising at least 25 genes. These patients share similar facial dysmorphisms with blepharophimosis, telecanthus, epicanthus, flat malar region, thin upper lip vermillion, down-turned corners of the mouth, and a poor facial movement/little facial expression. They have a moderate to severe developmental delay (4/4), absent speech (3/4), microcephaly (3/4), a history of seizures (3/4), postnatal short stature (2/4), and a diaphragmatic or hiatal hernia (2/4). Patient 5 was diagnosed with a smaller deletion of about 1.92 Mb (containing nine genes) localized within the deletion overlap of the other four patients. Patient 5 shows a different facial phenotype and a less severe mental retardation. In Patients 1-4, COH1 is involved in the deletion (in total or in part), but none of them showed clinical features of Cohen syndrome. In two patients (Patients 2 and 4), ZFPM2 (also called FOG2, a candidate gene for congenital diaphragmatic hernias) was partly deleted. We suggest that patients with a microdeletion of 8q22.2q22.3 may represent a clinically recognizable condition characterized particularly by the facial phenotype and developmental delay. More patients have to be evaluated to establish a phenotype-genotype correlation. © 2011 Wiley-Liss, Inc.

We report on three patients with probable cardio-facio-cutaneous (CFC) syndrome. They present clinical findings of this condition such as: growth failure, heart defects, typical craniofacial appearance, ectodermal abnormalities, and developmental delay. We also give a detailed review of the previously published articles on CFC syndrome and discuss the differences between CFC, Noonan, and Costello syndromes. Other differential diagnoses are considered.

We report on a 4-year-old boy with short stature, microcephaly, BNS (Blitz-Nick-Salaam) seizures, and global developmental delay. In addition, small and fleshy hands and feet as well as hypoplastic scrotum and testes were observed. The clinical features of the patient are compared with the patients previously described by Wiedemann et al. and Nevin et al. They reported three patients with a syndrome characterized by short stature, microcephaly, global developmental delay, abnormalities of hands and feet, seizures, large anterior fontanelle, scrotal hypoplasia, micropenis, cryptorchism, urinary tract abnormalities, and inguinal hernia (Wiedemann syndrome).

The previously undescribed combination of esophageal atresia, hypoplasia of the zygomatic complex, microcephaly, cup-shaped ears, congenital heart defect, and mental retardation was diagnosed in two siblings of different sexes, with the brother being more severely affected. The mother presented with zygomatic arch hypoplasia of the right side only. We discuss major differential diagnoses: Goldenhar, Feingold, CHARGE, and Treacher Collins syndromes show a few overlapping clinical features, but these diagnoses are unlikely as the clinical findings are unusual for Goldenhar syndrome and mutational screening of the MYCN, the CHD7, and the TCOF1 genes did not reveal any abnormalities. Autosomal recessive oto–facial syndrome, hypomandibular faciocranial dysostosis, and Ozkan syndromes were clinically excluded. A microdeletion 22q11.2 was excluded by FISH analysis, a microdeletion 2p23-p24 by microsatellite analyses, a subtelomeric chromosomal aberration by MLPA, and a small genomic deletion/duplication by CGH array. As X-inactivation studies did not show skewed X-inactivation in the mother, we consider X-chromosomal recessive inheritance of this condition less likely. We discuss autosomal dominant inheritance with variable expressivity or mosaicism in the mother as the likely genetic mechanism in this new multiple congenital anomaly/mental retardation (MCA/MR) syndrome. © 2007 Wiley-Liss, Inc.

Kabuki syndrome is a multiple congenital anomaly/mental retardation syndrome. This study of Kabuki syndrome had two objectives. The first was to further describe the syndrome features. In order to do so, clinical geneticists were asked to submit cases-providing clinical photographs and completing a phenotype questionnaire for individuals in whom they felt the diagnosis of Kabuki syndrome was secure. All submitted cases were reviewed by four diagnosticians familiar with Kabuki syndrome. The diagnosis was agreed upon in 48 previously unpublished individuals. Our data on these 48 individuals show that Kabuki syndrome variably affects the development and function of many organ systems. The second objective of the study was to explore possible etiological clues found in our data and from review of the literature. We discuss advanced paternal age, cytogenetic abnormalities, and familial cases, and explore syndromes with potentially informative overlapping features. We find support for a genetic etiology, with a probable autosomal dominant mode of inheritance, and speculate that there is involvement of the interferon regulatory factor 6 (IRF6) gene pathway. Very recently, a microduplication of 8p has been described in multiple affected individuals, the proportion of individuals with the duplication is yet to be determined.

We describe an 8.5-year-old boy with facial dysmorphism consisting of a round and flat face, telecanthus, periorbital fullness, short nose, downturned corners of the mouth, and micrognathia. In addition, profound mental retardation, tetralogy of Fallot, and renal dysplasia were present. Tentative clinical diagnoses during the 6-year follow-up included Down, Hennekam, and Noonan syndromes. Refinement of cytogenetic techniques, especially increase of banding resolution in conventional cytogenetic analysis, gave the clue to the correct diagnosis, which was proven by fluorescence in situ hybridization (FISH) with whole chromosome paints and single copy probes. We could show that he had an unbalanced translocation inherited from his father resulting in partial monosomy 18p and partial trisomy 20p. The combination of deletion 18p/duplication 20p was previously reported in three patients and seems to have a clinically recognizable face.

The previously unreported combination of bilateral absence of thumbs, aplasia of ulna at one and hypoplasia of ulna on the other side, retarded bone age, short stature, microcephaly, micropenis, cryptorchidism, and mental retardation is described in a 5-year-old boy. Having excluded major differential diagnoses, e.g. Fanconi anemia, RAPADILINO syndrome and VACTERL association, we hypothesize that this boy represents a new multiple congenital anomaly/mental retardation (MCA/MR) syndrome.

Human facial dysostoses comprise mandibulofacial (MFDs) and acrofacial dysostoses (AFDs). Both types are characterised by similar craniofacial dysmorphisms, which are assumed to be caused by an abnormal development of the neural crest cells. Craniofacial anomalies consist of downslanting palpebral fissures, lower eyelid coloboma with or without absence of lower eyelashes medial to the defect, hypoplasia of the zygomatic complex, micrognathia and microtia often associated with hearing loss. The facial anomalies are associated with limb anomalies in the AFDs, which are preaxial, postaxial or cannot be classified into one of these groups. The molecular basis for most of the MFDs and AFDs is unknown. For Treacher Collins syndrome (TCOF1, POLR1D and POLR1C) and MFD type Hutterite (TCOF1), the molecular basis is known which is also true for three of the AFDs, Nager syndrome (SF3B4), Miller syndrome (DHODH) and AFD type Guion-Almeida (EFTUD2). Key Concepts: In human facial dysostoses, the development of the structures of the first and second branchial arches is disturbed. Facial dysostoses can be subdivided into those with normal extremities, the mandibulofacial dysostoses (MFDs), and those with anomalies of limbs, the acrofacial dysostoses. TCOF1 mutations are causal for Treacher Collins syndrome and MFD type Hutterite. POLR1D and POLR1C mutations are causal for Treacher Collins syndrome. SF3B4 mutations are causal for Nager syndrome. EFTUD2 mutations are causal for ADGA. DHODH mutations are causal for Miller syndrome. EVC and EVC2 mutations are causal for Weyers syndrome. Keywords: mandibulofacial dysostosis; acrofacial dysostosis; Nager syndrome; Miller syndrome; acrofacial dysostosis type Guion-Almeida; spliceosome; Treacher Collins syndrome; MFD type Hutterite

We describe three brothers from a non-consanguineous family with microcephaly, mental and physical retardation, speech disorder, facial anomalies, and internal hydrocephalus in two of the three affected brothers. The youngest brother died at the age of 5 months. He had situs abdominalis inversus, ASD II, and had been operated for internal hydrocephalus and atresia of the biliary duct. A search in the Oxford Medical Database Dysmorphology Program suggested phenotypic similarities with two sisters described in 1972 by Osvaldo Mutchinick in Argentina. Although differences in their phenotypes exist, it is possible that the two sets of sibs represent the same, rare syndrome. This interpretation is supported by the origin of both families from the same geographic region. Am. J. Med. Genet. 73:210–216, 1997. © 1997 Wiley-Liss, Inc.

We report on a 4-month-old boy with a de novo interstitial deletion of the short arm of chromosome 3 (pter {r_arrow} p21.2::p12 {r_arrow} qter) and clinical findings typical of proximal 3p deletion together with coloboma of iris, heart defect, choanal atresia, retardation of growth and development, genital hypoplasia, and ear anomalies. Family history was unremarkable and parental chromosomes were normal. The clinical manifestations of the patient are compared with those of 10 patients previously described with a proximal 3p deletion. The additional CHARGE- like phenotype is discussed. 20 refs., 4 figs., 1 tab.