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We describe two patients with upper eyelid coloboma, hypertelorism, disruption of the eyebrow, and anterior hairline anomaly. The phenotype in our patients is consistent with Manitoba Oculotrichoanal syndrome (MOTA syndrome, OMIM 248450), which comprises a variable spectrum of eyelid malformations ranging from cryptophthalmos to upper eyelid colobomas; aberrant ipsilateral anterior hairline, and anal anomalies. It was first described in members of the indigenous population of the Island Lake region of Northern Manitoba, Canada. Autosomal recessive inheritance is demonstrated in these families and single-gene etiology has been proposed. This constellation of anomalies also corresponds to those arising from the Number 10 cleft in Tessier's anatomical classification of clefting malformations. Tessier Number 10 clefts are the rarest of the 15 craniofacial clefting malformations first described by Tessier [Tessier (1976); J Maxillofac Surg 4:69-92]. They have only ever been reported as sporadic occurrences and the underlying etiology is thought to be environmental. We believe the phenotype in our patients and in those previously described with MOTA syndrome represents a disorder of craniofacial clefting; specifically, one that occurs along the tissue planes of the Tessier Number 10 cleft. The familial clustering of these facial features and their variable association with other congenital anomalies supports a genetic rather than environmental cause. The mapping of the gene for this syndrome is likely to involve a combined functional and positional approach with a focus on candidate genes involved in craniofacial development.

Anophthalmia and pituitary gland hypoplasia are both debilitating conditions where the underlying genetic defect is unknown in the majority of cases. We identified a patient with bilateral anophthalmia and absence of the optic nerves, chiasm and tracts, as well as pituitary gland hypoplasia and ear anomalies with a de novo apparently balanced chromosomal translocation, 46,XY,t(3;14)(q28;q23.2). Translocation breakpoint analysis using FISH and high-resolution microarray comparative genomic hybridization (CGH) has identified a 9.66 Mb deleted region on the long arm of chromosome 14 which includes the genes BMP4, OTX2, RTN1, SIX6, SIX1, and SIX4. Three other patients with interstitial deletions involving 14q22-23 have been described, all with bilateral anophthalmia, pituitary abnormalities, ear anomalies, and a facial phenotype similar to our patient. OTX2 is involved in ocular developmental defects, and the severity of the ocular phenotype in our patient and the other 14q22-23 deletion patients, suggests this genomic region harbors other gene/s involved in ocular development. BMP4 haploinsufficiency is predicted to contribute to the ocular phenotype on the basis of its expression pattern and observed murine mutant phenotypes. In addition, deletion of BMP4 and SIX6 is likely to contribute to the abnormal pituitary development, and SIX1 deletion may contribute to the ear and other craniofacial features. This indicates that contiguous gene deletion may contribute to the phenotypic features in the 14q22-23 deletion patients.

Amelogenesis imperfecta hypoplastic-hypomaturation with taurodontism (AIHHT) is an autosomal dominant (AD) trait associated with enamel defects and enlarged pulp chambers. In this study, we mapped an AIHHT family to human chromosome 17 q21-q22 (lod score 3.3) and identify a two basepair deletion (CT) at nucleotide 560 in DLX3 associated with the disease. This mutation causes a frameshift altering the last two amino acids of the DNA-binding homeodomain introducing a premature stop codon truncating the protein by 88 amino acids. This is the first report of a mutation within the homeodomain of DLX3. Previous studies have shown a DLX3 mutation outside the homeodomain associated with tricho-dento-osseous syndrome (TDO) suggesting TDO and some forms of AIHHT are allelic., ((c) 2005 Wiley-Liss, Inc.)

This study was undertaken to document the phenotype of Kabuki (Niikawa-Kuroki) syndrome in patients from Australia and New Zealand, with particular emphasis on growth patterns, behavior, and relationship between head circumference and intellectual level. Data on 27 children and adults with Kabuki (Niikawa-Kuroki) syndrome from Australia and New Zealand were collected by questionnaire and clinical assessment. The patients ranged in age from 7 months to 36 years with a mean age of 7 years and 2 months. The mean age at diagnosis was 3(5/6) years, but in most cases, the facial phenotype was evident from infancy. The minimum birth prevalence was calculated at 1 in 86,000. Three of our patients died. Parents reported a behavior phenotype characterized by an excellent long-term memory and avoidance of eye contact. No correlation was found between head circumference and severity of intellectual disability. Eight of 14 patients over the age of 5 years were overweight or obese. Six of these eight patients had failure to thrive in infancy. One patient developed insulin-dependent diabetes mellitus in adolescence. Some individuals with Kabuki (Niikawa-Kuroki) syndrome show a characteristic growth profile with failure to thrive in infancy progressing to obesity or overweight in middle childhood or adolescence. A behavior phenotype was noted which requires further investigation. Head size is not a predictor of degree of intellectual disability., (Copyright 2004 Wiley-Liss, Inc.)