{'fraction_non_alphanumeric': 0.030974632843791722, 'fraction_numerical': 0.023230974632843793, 'mean_word_length': 5.737410071942446, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Brachyolmia with amelogenesis imperfecta: Further evidence of a distinct entity

Brachyolmia is a heterogeneous group of skeletal dysplasia characterized by generalized platyspondyly without significant epiphyseal or metaphyseal involvement. Several types of brachyolmia were described based on the radiographic appearance of the vertebral bodies, associated findings and mode of inheritance [Shohat et al., 1989]: (1) Hobaek (OMIM 271530) and Toledo (OMIM 271630) types are both autosomal recessive disorders comprising similar skeletal findings—universal generalized platyspondyly, irregular and reduced intervertebral spaces and marked extension of the lateral margins of the vertebrae—and abnormal qualitative excretion of glycosaminoglycans (GAG). However, the presence of corneal opacities and precocious ossification of costal cartilage differentiates the Toledo type [Toledo, 1996] from the former. (2) The Maroteaux type is an autosomal recessive form of brachyolmia distinguished by the rounded aspect of the anterior and posterior vertebral borders and less elongated vertebral bodies, compared to the previous types. (3) The dominant type (OMIM 113500) is rare, with only three families reported in the literature. Some affected patients show the more severe platyspondyly. Recently, Rock et al. [2007] described at the 8th Meeting of the International Skeletal Dysplasia Society a four generation family with additional findings and suggested genetic heterogeneity within autosomal dominant brachyolmia. In 1996, Verloes et al. described a further type of brachyolmia, possibly autosomal recessive (OMIM 601216). In their report, two siblings born from a consanguineous Moroccan couple presented platyspondyly associated with amelogenesis imperfecta. Recently, the gene TRPV4, which encodes a calcium permeable cation channel, was reported as the responsible for the autosomal dominant form of brachyolmia in two families [Rock et al., 2008]. The molecular basis of the recessive forms remains to be clarified. We report on another three affected patients (two siblings and one unrelated patient), also from consanguineous matings, presenting brachyolmia with enamel defects, giving further support to the fact that these findings represent a single entity. In the first family, two siblings (a 26and a 17-year-old male) born from first-cousin parents are affected. Both were born at term, by vaginal delivery, with a length of 46 cm. The older patient was evaluated in the Genetics Unit at age 14, complaining of back pain with radiological evidence of scoliosis since 10 years of age, short stature and dental anomalies, mainly oligodontia and abnormal coloration of the teeth. The physical exam at 14y3mo showed a W1⁄4 46.6 kg (25th–50th centile); H1⁄4 138 cm (<2.5nd centile); OFC1⁄4 57 cm (50th–98th centile); disproportionate short stature, with a short trunk and scoliosis and normal hand measurements. He presented normal hair and nails. Odontologic evaluation disclosed olygodontia and enamel hypoplasia. Complementary exams revealed a normal abdominal ultrasound, echocardiogram and urinary excretion of GAG, including qualitative analysis of chondroitin sulfate. Ophthalmologic exam was normal except for myopia. Skeletal survey showed striking spine anomalies, including generalized platyspondyly, with rounding of the anterior borders of the vertebral bodies, narrow intervertebral distance, short pedicles, posterior scalloping and herniation of the nuclei, besides scoliosis. Other findings were short ilia, with shortening of the sacroiliac notches and broad and short femoral necks (Fig. 1A). Neither metaphyseal nor epiphyseal involvements were observed. Orthopantographic study disclosed agenesis of several teeth