PHENOTYPIC SPECTRUM OF CHARGE SYNDROME WITH CHD7 MUTATIONS
MICHIHIKO ARAMAKI, MD, TORU UDAKA, MS, RIKA KOSAKI, MD, YOSHIO MAKITA, MD, NOBUHIKO OKAMOTO, MD,
HIROSHI YOSHIHASHI, MD, HIROTAKA OKI, MD, KENJI NANAO, MD, NOBUKO MORIYAMA, MD, SHOZO OKU, MD,
TOMONOBU HASEGAWA, MD, TAKAO TAKAHASHI, MD, YOSHIMITSU FUKUSHIMA, MD, HIROSHI KAWAME, MD, AND KENJIRO KOSAKI, MD
CHD7 gene mutations were identified in 17 (71%) of 24 children clinically diagnosed to have CHARGE syndrome (C,
coloboma of the iris or retina; H, heart defects; A, atresia of the choanae; R, retardation of growth and/or development; G,
genital anomalies; and E, ear abnormalities). Colobomata, hearing loss, laryngomalacia, and vestibulo-cochlear defect were
prevalent. Molecular testing for CHD7 enables an accurate diagnosis and provides health anticipatory guidance and genetic
counseling to families with CHARGE syndrome. (J Pediatr 2006;148:410-4)
T
wenty-five years ago, Hall
1
documented in The Journal of Pediatrics that choanal atresia and ocular colomba can be
associated with a specific pattern of malformations. Two years later, in the same journal, Pagon et al coined the term
CHARGE to represent a constellation of non-randomly associated malformations: C, coloboma of the iris or retina; H,
heart defects; A, atresia of the choanae; R, retardation of growth and/or development; G, genital anomalies; and E, ear
abnormalities.
2
Recently, Vissers et al
3
identified the gene Chromodomain helicase DNA-
binding protein-7 (CHD7) at chromosome 8q12.1 as a causative gene of CHARGE
association. Now that the underlying cause is known in most cases, the entity is referred
to as CHARGE syndrome rather than CHARGE association. According to their study,
12 of 19 (63%) of their patients had heterozygous mutations in CHD7. Here, we further
delineate the phenotypic spectrum of CHARGE syndrome patients with mutations in
CHD7.
METHODS
The subjects were recruited from a group of patients with CHARGE syndrome
who were regularly followed at the authors’ institutions at the time of study (August 2004
to March 2005). A diagnosis of CHARGE syndrome was made according to the criteria
defined by Blake et al.
4
Blake’s major criteria are coloboma or microphthalmia, choanal
atresia or stenosis, typical ear anomalies, and cranial nerve dysfunction. Choanal atresia
was diagnosed by CT scan. The minor criteria are genital hypoplasia, delayed develop-
ment, cardiovascular malformations, growth deficiency, orofacial cleft, tracheoesophageal
fistula, and distinctive face characteristics. Twenty-three patients who fulfilled Blake’s
criteria (4 major or 3 major plus 3 or more minor criteria) and 1 patient who fulfilled 2
major and 6 minor criteria
4
were included in the study: All the patients were unrelated and
simplex case (ie, a single occurrence in a family). Each patient and family members were
enrolled in the study after receiving their written informed consent, according to a
protocol approved by an institutional review board.
The entire CHD7 coding region (exons 2-38) was screened for mutations. The
primer pairs, which were designed to amplify exons, exon-intron boundaries, and short
flanking intronic sequences, are available on request. Polymerase chain reaction (PCR)
amplicons from genomic DNA were scanned for mutations using DNA high-perfor-
mance liquid chromatography (DHPLC, Transgenomic, Omaha, Nebraska), as described
previously.
5
PCR products corresponding to all variant elution profiles of the DHPLC
were purified by using a desalting column and were sequenced bidirectionally by using the
DHPLC DNA high-performance liquid
chromatography
PCR Polymerase chain reaction
From the Department of Pediatrics, Keio
University School of Medicine, Tokyo, Ja-
pan; the Department of Clinical Genetics
and Molecular Medicine, National Chil-
dren’s Medical Center, Tokyo, Japan; the
Department of Pediatrics, Asahikawa Med-
ical College, Asahikawa, Japan; the Depart-
ment of Planning and Research, Osaka
Medical Center and Research Institute for
Maternal and Child Health, Osaka, Japan;
the Departments of Neonatology and Car-
diology, Tokyo Metropolitan Kiyose Chil-
dren’s Hospital, Tokyo, Japan; the Depart-
ment of Pediatrics, Yamato Municipal
Hospital, Kanagawa, Japan; the Department
of Pediatrics, Ibaraki Children’s, Ibaraki, Ja-
pan; the Department of Pediatrics, Ka-
goshima City Hospital, Kagoshima, Japan;
and the Department of Medical Genetics,
Shinshu University School of Medicine and
Division of Clinical Genetics, Nagano Chil-
dren’s Hospital, Nagano, Japan.
Contract grant sponsors were The Ministry
of Health, Labour, and Welfare of Japan.
T.U. was supported by a research grant
from Transgenomic, Inc, Omaha, Nebraska,
whose machine was used to analyze the
patients’ genomic DNA in the study.
Submitted for publication Apr 5, 2005; last
revision received Oct 2, 2005; accepted
Oct 21, 2005.
Reprint requests: Dr Kenjiro Kosaki, Divi-
sion of Medical Genetics, Department of
Pediatrics, Keio University School of Medi-
cine, 35 Shinanomachi, Shinjuku-ku, Tokyo
160 – 8582, Japan.
0022-3476/$ - see front matter
Copyright © 2006 Elsevier Inc. All rights
reserved.
10.1016/j.jpeds.2005.10.044
410