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CLINICAL REPORT

Congenital Heart Defects in OculodentodigitalDysplasia: Report of Two Cases

Kosuke Izumi, Andrew M. Lippa, Alisha Wilkens, Holly A. Feret, Donna M. McDonald-McGinn,and Elaine H. Zackai*Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania

Manuscript Received: 24 February 2013; Manuscript Accepted: 10 June 201

3

How to Cite this Article:Izumi K, Lippa AM, Wilkens A, Feret HA,

McDonald-McGinn DM, Zackai EH. 2013.

Congenital heart defects in

oculodentodigital dysplasia: report of two

cases.

Am J Med Genet Part A 161A:3150–3154.

Oculodentodigital dysplasia is caused by mutations in the GJA1

gene. Oculodentodigital dysplasia presents with a spectrum of

clinical features including craniofacial, ocular, dental, and limb

anomalies. Although recent findings implicate the major role of

GJA1 during cardiac organogenesis, congenital heart defects are

infrequently reported in oculodentodigital dysplasia. Here we

report on two patients with GJA1 mutations presenting with

cardiac malformations and type III syndactyly. Patient 1 pre-

sented with pulmonary atresia, an intact septum, right ventricu-

lar hypoplasia and tricuspid stenosis. The infant had a small

nose, thin columella and bilateral 4–5 syndactyly of the fingers. A

denovo c.226C>T (p.Arg76Cys)mutationwas identified. Patient

2presented at 6monthswithaventricular septal defect. The child

had hypoplastic alae nasi with a thin columella and bilateral 4–5

syndactyly of the digits. A de novomissensemutation, c.145C>G

(p.Gln49Glu) was found. Our two patients underscore the

importance of cardiac evaluations as part of the initial workup

for patients with findings of oculodentodigital dysplasia. Con-

versely, those patients with type III syndactyly and congenital

heart defect should be screened for GJA1mutations. � 2013Wiley

Periodicals, Inc.

Key words: GJA1; pulmonary stenosis; ventricular septal defect

�Correspondence to:

Elaine H. Zackai, Department of Clinical Genetics, Children’s Hospital

of Philadelphia, 3401 Civic Center Blvd., 8 Central, Room 8C05,

Philadelphia, PA 19104.

E-mail: zackai@email.chop.edu

Article first published online in Wiley Online Library

(wileyonlinelibrary.com): 2 October 2013

DOI 10.1002/ajmg.a.36159

INTRODUCTION

Oculodentodigital dysplasia (ODDD) (OMIM 164200) is charac-

terized by dysmorphic facial features, ocular and dental anomalies

and syndactyly. ODDD is caused by mutations in GJA1, which is

also known as Cx43, and it encodes gap junction protein alpha 1

(connexin 43), a member of connexin protein family [Paznekas

et al., 2003]. The majority of the previously reported mutations

were missense mutations, suggesting the mechanism of ODDD is

due to dominant negative effect of GJA1 rather than haploinsuffi-

ciency of GJA1 [Flenniken et al., 2005].

There has been growing interests in the role of GJA1 in cardi-

omyocytes, because of connexins’ essential role in cardiac action

potential propagation. In fact, GJA1 is strongly expressed in the

heart and connexin 43 is one of the most predominant connexin

proteins in the heart [Coppen et al., 2003]. In addition to its role in

action potential propagation, mice models with Cx43 mutations

haveproved themajor role ofGJA1 in cardiacmorphogenesis, given

2013 Wiley Periodicals, Inc.

the cardiac malformations seen in Gja1 mutant animals [Reaume

et al., 1995; Ya et al., 1998; Yu et al., 2004]. Furthermore, human

mutationsofGJA1were also reported in individualswith congenital

heart disease (CHD) (ventricular septal defect [VSD], tetralogy of

Fallot, hypoplastic left heart syndrome, and heterotaxy) [Britz-

Cunningham et al., 1995; Dasgupta et al., 2001; Wang et al., 2010].

Such observations indicate that the perturbation of connexin43

function is detrimental to the cardiogenesis even in human.

On the contrary, CHD is not considered to be associated with

ODDD, and the cardiac defects have only been limited to several

patients with ODDD. We recently identified two patients with

ODDDwhohaveCHD.The purpose of this report is to describe the

spectrum of CHDs seen as a part of ODDD phenotype.

CLINICAL REPORT

Patient 1 was a newbornmale infant whowas born to a 29-year-old

G3P2–3 mother. The pregnancy was complicated by gestational

diabetes and prenatal detection of fetal cardiac malformations

including pulmonary atresia with intact ventricular septum. He

was delivered by spontaneous vaginal delivery at 3937= weeks of

gestation. Family history is remarkable for the paternal history of

cardiomegaly of unknown etiology. The birth weight was 75th

3150

IZUMI ET AL. 3151

centile, length was 70th centile, and head circumference was 90th

centile. At birth, he required prostaglandin E1 for the management

of his CHD. Physical examination demonstrated facial dysmor-

phisms including frontal upsweep, small nose, small alae nasi with

thin columellawhichwent below thenares andbilateral cupped ears

with notched superior helices on the left ear. Cardiac exam revealed

3/6 systolicmurmur heard loudest at the right lower sternal boarder

with radiation throughout precordium. In addition, bilateral cuta-

neous syndactyly of the 4th and 5th fingers as well as single palmer

creases were noted. Ophthalmologic examination was unremark-

able except for narrow horizontal palpebral fissure length and

telecanthus. Given his facial dysmorphisms and the pattern of

syndactyly, the clinical diagnosis of ODDD was given. For the

molecular confirmation of the diagnosis,GJA1 sequencing analysis

revealed a de novo heterozygous missense mutation, c.226C>T (p.

Arg76Cys). The same missense change has not been reported,

however, two disease causing mutations have been reported at

this position [Pizzuti et al., 2004; Paznekas et al., 2009].

Postnatal cardiac examination confirmed the prenatal findings.

Chest X-ray at birth demonstrated cardiomegaly with an absent

pulmonary artery segment. Pulmonary vascularity was diminished

(Fig. 1A). Echocardiography confirmed pulmonary atresia with an

intact ventricular septum with a very hypoplastic right ventricle

(Fig. 1B). At 6 days of life, he underwent a Blalock–Taussig shunt

procedure. His post-surgical course was complicated by arrhyth-

mia, cardiorespiratory arrest, which necessitated prolonged chest

compressions and subsequent extracorporeal membrane oxygen-

ationutilization.Healsowas found tohavebilateralmiddle cerebral

artery watershed distribution infarcts that caused seizures. Subse-

quently, he expired at 3 months of age.

Patient 2was referred to theGenetics clinic at the age of 6months

due to bilateral 4–5 syndactyly, VSD and failure to thrive. She was

born to a G1P0–1 mother following an uncomplicated 39-week

pregnancy. She was delivered by cesarean due to breech presenta-

tion. Her birth weight was 30th centile. The family history is non-

contributory. VSD was diagnosed at the age of 2 months due to the

FIG. 1. Clinical features of Patient 1. A: Chest X-ray at birth. B: Echocard

presence of a murmur. Chest X-ray revealed cardiomegaly, and an

echocardiogram demonstrated a moderate size conoventricular

VSD (Fig. 2A).With the development of cardiac failure symptoms,

she underwent surgical closure of VSD at the age of 6 months.

At the age of 9 months, her weight was 10th centile, length was

75th centile and head circumference was 25th centile. Physical

examination revealed hypertelorismwith interpupillary distance of

97th centile, hypoplastic alae nasi with a thin columella extending

below the nares as well as bilateral 4th and 5th finger syndactyly

(Fig. 2B). Ophthalmology exam was remarkable for hyperopia.

Genome-wide SNP array was normal. Given the combination of

facial dysmorphisms and type III syndactyly, diagnosis of ODDD

was suspected, and GJA1 sequencing analysis revealed a de novo

heterozygous missense mutation, c.145C>G (p.Gln49Glu). This

mutation has not been described previously, but other missense

substitutions at this position have been reported [Paznekas

et al., 2003, 2009].

DISCUSSION

Here we describe two individuals with ODDD andCHD. Given the

well-documented function of GJA1 in cardiac morphogenesis and

myocardial function, it is not surprising that CHDs could be found

in association with the ODDD phenotype, although previous

reports concluded that CHDs are not common in individuals

with ODDD. However, when combining the previously reported

cases of ODDD, the prevalence of CHDs was estimated as 3–10%,

which is infrequent, but higher than the incidence of CHDs in the

general population (0.8–1.5%), suggesting the association between

ODDD and CHD [Reller et al., 2008; Moons et al., 2009; Paznekas

et al., 2009; Yu et al., 2011].

Aside from the two cases reported herein, seven patients with

ODDDwere reported with CHD, ranging from pulmonic stenosis

to atrial orVSDs (Fig. 3 andTable I) [Schneider et al., 1977; Judisch

et al., 1979; Paznekas et al., 2003, 2009; van Es et al., 2007]. The

pattern of CHD seen in our cases fits within this clinical spectrum,

iography result demonstrating a very hypoplastic right ventricle.

FIG. 2. Clinical features of Patient 2. A: Chest X-ray. B: Hand anomalies of Patient 2.

3152 AMERICAN JOURNAL OF MEDICAL GENETICS PART A

although the cardiac phenotype observed in Patient 1 appears to be

the most severe type of CHD among individuals with ODDD to

date. We propose that pulmonic stenosis and septal defects be

regarded as the characteristic patterns of CHD in ODDD. It is of

particular interest to note that pulmonary stenosis is the most

frequent heart problem in ODDD, and previously, Cx43 null mice

demonstrated failed pulmonary gas exchange due to pulmonary

stenosis [Reaume et al., 1995]. Since the mechanism of GJA1

FIG. 3. Location of GJA1 mutations associated with CHD. G21R was repo

in Paznekas et al. [2009].

missense mutations found in ODDD patients is due to its domi-

nant negative effect, some ODDD missense mutations associated

with pulmonary stenosis phenotype may cause nearly complete

absence of functional connexin43 due to the dominant negative

effect.

Hitherto, three mouse models possessing Cx43 missense muta-

tion, which cause dominant negative effect, have been created

[Flenniken et al., 2005; Kalcheva et al., 2007; Dobrowolski

rted in Paznekas et al. [2003]. V96A, T154A and R202H were reported

TABLE I. Previously Reported Congenital Heart Defects in Patients with ODDD

Cardiac defect (number of cases) GJA1 mutation (number of cases)

Pulmonic stenosis (3) R202H extra cellular (2) Paznekas et al. [2003, 2009]

V96A transmembrane Paznekas et al. [2009]

VSD (2) T154A cytoplasmic van Es et al. [2007], Paznekas et al. [2009]

Prior to the gene identification Judisch et al. [1979]

ASD (2) G21R transmembrane Paznekas et al. [2003]

Prior to the gene identification Schneider et al. [1977]

IZUMI ET AL. 3153

et al., 2008]. Although these three mouse lines demonstrated

characteristic phenotypic features resembling that of ODDD, nei-

ther model demonstrated structural cardiac abnormalities, except

for patent foramen ovale [Flenniken et al., 2005]. The explanation

for the absence of structural cardiac anomalies in missense muta-

tion mouse models remains unknown. Since the mutant mouse

Cx43 model does not completely recapitulate its pleiotropic phe-

notype of ODDD, as demonstrated by the absence of conductive

hearing loss or neurological phenotype, the absence of CHD

phenotype may suggest that the human is more susceptible to

develop CHD in an association with GJA1mutations than mouse.

Alternatively, the GJA1 mutations found in ODDD patients with

CHD may serve as risk factors for developing CHD, where addi-

tional events (i.e., second hit genetic mutation) may be required to

cause CHD.

Although CHDs are not observed in these missense mutation

mouse models, functional cardiac phenotypes such as abnormal

cardiac conduction and arrhythmia, were seen in ODDD mutant

mice, and this observation is in agreement with the previous report

of human ODDD patients with arrhythmia [Paznekas et al., 2003;

Flenniken et al., 2005; Kalcheva et al., 2007; Dobrowolski et al.,

2008]. Therefore, close attention should be paid to cardiac func-

tional abnormalities in patients with ODDD. Hence, we recom-

mend close cardiac longitudinal follow up after the initial screening

of CHD.

Here we describe our two patients with ODDD, who have

CHD, and summarize the spectrum of CHDs reported in

ODDD. Although CHDs are not frequently seen in ODDD with

GJA1 mutations, our two cases, together with those previously

reported, support cardiac evaluations as part of the initial workup

forpatientswithfindingsofODDD.Conversely, thosepatientswith

syndactyly of digits 4–5 and CHD should be screened for GJA1

mutations.

REFERENCES

Britz-Cunningham SH, Shah MM, Zuppan CW, Fletcher WH. 1995.Mutations of the Connexin43 gap-junction gene in patients withheart malformations and defects of laterality. N Engl J Med 332:1323–1329.

Coppen SR, Kaba RA, Halliday D, Dupont E, Skepper JN, Elneil S,Severs NJ. 2003. Comparison of connexin expression patterns in thedeveloping mouse heart and human foetal heart. Mol Cell Biochem242:121–127.

Dasgupta C, Martinez AM, Zuppan CW, Shah MM, Bailey LL, FletcherWH. 2001. Identification of connexin43 (alpha1) gap junction gene

mutations in patients with hypoplastic left heart syndromeby denaturinggradient gel electrophoresis (DGGE). Mutat Res 479:173–186.

Dobrowolski R, Sasse P, Schrickel JW, Watkins M, Kim JS, RackauskasM, Troatz C, Ghanem A, Tiemann K, Degen J, Bukauskas FF, CivitelliR, Lewalter T, Fleischmann BK, Willecke K. 2008. The conditionalconnexin43G138R mouse mutant represents a new model of heredi-tary oculodentodigital dysplasia in humans. Hum Mol Genet 17:539–554.

Flenniken AM, Osborne LR, Anderson N, Ciliberti N, Fleming C, GittensJE,GongXQ,KelseyLB, LounsburyC,MorenoL,NiemanBJ,PetersonK,QuD, RoscoeW, ShaoQ, Tong D, Veitch GI, Voronina I, VukobradovicI,Wood GA, Zhu Y, Zirngibl RA, Aubin JE, Bai D, Bruneau BG, GrynpasM, Henderson JE, Henkelman RM, McKerlie C, Sled JG, Stanford WL,Laird DW, Kidder GM, Adamson SL, Rossant J. 2005. A GJA1 missensemutation in amousemodel of oculodentodigital dysplasia.Development132:4375–4386.

Judisch GF, Martin-Casals A, Hanson JW, Olin WH. 1979. Oculodento-digital dysplasia. Four new reports and a literature review. Arch Oph-thalmol 97:878–884.

Kalcheva N, Qu J, Sandeep N, Garcia L, Zhang J, Wang Z, Lampe PD,Suadicani SO, Spray DC, Fishman GI. 2007. Gap junction remodelingand cardiac arrhythmogenesis in a murine model of oculodentodigitaldysplasia. Proc Natl Acad Sci USA 104:20512–20516.

Moons P, Sluysmans T, DeWolf D, Massin M, Suys B, Benatar A, GewilligM. 2009. Congenital heart disease in 111 225 births in Belgium: Birthprevalence, treatment and survival in the 21st century. Acta Paediatr98:472–477.

PaznekasWA,Boyadjiev SA, ShapiroRE,DanielsO,WollnikB,KeeganCE,Innis JW, Dinulos MB, Christian C, Hannibal MC, Jabs EW. 2003.Connexin 43 (GJA1) mutations cause the pleiotropic phenotype ofoculodentodigital dysplasia. Am J Hum Genet 72:408–418.

Paznekas WA, Karczeski B, Vermeer S, Lowry RB, Delatycki M, Lau-rence F, Koivisto PA, Van Maldergem L, Boyadjiev SA, Bodurtha JN,Jabs EW. 2009. GJA1 mutations, variants, and connexin 43 dysfunc-tion as it relates to the oculodentodigital dysplasia phenotype. HumMutat 30:724–733.

Pizzuti A, Flex E,Mingarelli R, Salpietro C, Zelante L, Dallapiccola B. 2004.A homozygous GJA1 genemutation causes aHallermann-Streiff/ODDDspectrum phenotype. Hum Mutat 23:286.

Reaume AG, de Sousa PA, Kulkarni S, Langille BL, Zhu D, Davies TC,Juneja SC, Kidder GM, Rossant J. 1995. Cardiac malformation inneonatal mice lacking connexin43. Science 267:1831–1834.

RellerMD, StricklandMJ, Riehle-Colarusso T,MahleWT, Correa A. 2008.Prevalence of congenital heart defects in metropolitan Atlanta, 1998–2005. J Pediatr 153:807–813.

Schneider JA, Shaw GG, Van Reken DE. 1977. Congenital heart disease inoculodentodigital dysplasia. Va Med 104:262–263.

van Es RJ,Wittebol-Post D, Beemer FA. 2007. Oculodentodigital dysplasiawithmandibular retrognathism and absence of syndactyly: A case report

3154 AMERICAN JOURNAL OF MEDICAL GENETICS PART A

with a novelmutation in the connexin 43 gene. Int JOralMaxillofac Surg36:858–860.

WangB,WenQ,XieX, Liu S, LiuM,TaoY, Li Z, SuoP, ShenA,Wang J,MaX. 2010.Mutation analysis of Connexon43 gene in Chinese patients withcongenital heart defects. Int J Cardiol 145:487–489.

Ya J, Erdtsieck-ErnsteEB, deBoerPA, vanKempenMJ, JongsmaH,GrosD,Moorman AF, Lamers WH. 1998. Heart defects in connexin43-deficientmice. Circ Res 23:360–366.

YuQ, ShenY,Chatterjee B, Siegfried BH, Leatherbury L, Rosenthal J, LucasJF, Wessels A, Spurney CF, Wu YJ, Kirby ML, Svenson K, Lo CW. 2004.ENU induced mutations causing congenital cardiovascular anomalies.Development 131:6211–6223.

Yu Z, Xi Y, Ding W, Han S, Cao L, Zhu C, Wang X, Guo X. 2011.Congenital heart disease in a Chinese hospital: Pre- and postnataldetection, incidence, clinical characteristics and outcomes. Pediatr Int53:1059–1065.