TY - JOUR
T1 - New Insights into Kleefstra Syndrome
T2 - Report of Two Novel Cases with Previously Unreported Features and Literature Review
AU - Ciaccio, Claudia
AU - Scuvera, Giulietta
AU - Tucci, Arianna
AU - Gentilin, Barbara
AU - Baccarin, Marco
AU - Marchisio, Paola
AU - Avignone, Sabrina
AU - Milani, Donatella
PY - 2018
Y1 - 2018
N2 - Kleefstra syndrome (KS) is a rare genetic condition resulting from either 9q34.3 microdeletions or mutations in the EHMT1 gene located in the same genomic region. To date, approximately 100 patients have been reported, thereby allowing the core phenotype of KS to be defined as developmental delay/intellectual disability, generalized hypotonia, neuropsychiatric anomalies, and a distinctive facial appearance. Here, to further expand the knowledge on genotype and phenotype of this condition, we report 2 novel cases: one patient carrying a 46-kb 9q34.3 deletion and showing macrocephaly never described in KS, and a second patient carrying a classic 9q34.3 deletion, presenting with a previously unreported skeletal feature (postaxial polydactyly of the right foot) and an unusual brain anomaly (olfactory bulb hypoplasia) observed via magnetic resonance imaging. Further, we provide a review of the current literature regarding KS and compare these 2 patients with those previously described, thereby confirming that the genotype-phenotype correlation in KS remains difficult to determine.
AB - Kleefstra syndrome (KS) is a rare genetic condition resulting from either 9q34.3 microdeletions or mutations in the EHMT1 gene located in the same genomic region. To date, approximately 100 patients have been reported, thereby allowing the core phenotype of KS to be defined as developmental delay/intellectual disability, generalized hypotonia, neuropsychiatric anomalies, and a distinctive facial appearance. Here, to further expand the knowledge on genotype and phenotype of this condition, we report 2 novel cases: one patient carrying a 46-kb 9q34.3 deletion and showing macrocephaly never described in KS, and a second patient carrying a classic 9q34.3 deletion, presenting with a previously unreported skeletal feature (postaxial polydactyly of the right foot) and an unusual brain anomaly (olfactory bulb hypoplasia) observed via magnetic resonance imaging. Further, we provide a review of the current literature regarding KS and compare these 2 patients with those previously described, thereby confirming that the genotype-phenotype correlation in KS remains difficult to determine.
KW - 9q34.3
KW - <italic>EHMT1</italic>
KW - Developmental delay
KW - Kleefstra syndrome
KW - Olfactory bulbs
KW - Polydactyly
UR - http://www.scopus.com/inward/record.url?scp=85056990792&partnerID=8YFLogxK
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U2 - 10.1159/000494532
DO - 10.1159/000494532
M3 - Article
AN - SCOPUS:85056990792
VL - 156
SP - 127
EP - 133
JO - Cytogenetic and Genome Research
JF - Cytogenetic and Genome Research
SN - 1424-8581
IS - 3
ER -