The Schwartz-Jampel syndrome (SJS) is a rare congenital multisystem disorder of unknown pathogenesis which is characterized by distinct faces, skeletal deformities, joint contractures, short stature, muscle hypertrophy, clinical myotonia, and continuous muscle fiber activity. The inheritance pat- tern of SJS has been assumed to be autosomal recessive. We report the occurrence of the classic SJS syndrome in both a father and son in a non- consanguineous family, suggesting that SJS has the potential for a domi- nant pattern of inheritance. Key words: Schwartz-Jampel syndrome skeletal deformities myotonia muscle fiber activity, continuous MUSCLE & NERVE 13:1152-1163 1990 z IH SCHWARTZ- JAMPEL SYNDROME WITH DOMINANT INHERITANCE ROBERT M. PASCUZZI, MD, ROBERTO GRATIANNE, MD, BlAGlO AZZARELLI, MD, and JOHN C. KINCAID, MD zyxwvut A Sc1iwarts-Jampcl syntironicr is zyxwvu MLKJIH ;i r-aiv ciisorcler of iinkiiowii pathogenesis cliarncterizctl by skeletal tie form itics , slio r t stat 11 re , joint coi 1 t i xt u res , 171 its- c:le liypertr-ophy, cliai-actci-istic fiicics, riiusclc stiff- ness, clinical niyotonia, arid contiiiuous muscle fi- ber activity. Schwar-tz mid Jmipcl, who iq>oitcd two siblings in 1962 with the c a r d i d manifcst;i- tions of the synclrome, einphasizetl the ocular findings of n a r r o w palpebral zyxwvu IHGFED fissures, tcr-met1 I)lc~~I~ai.o~'hitn(,sis."' 'rile iriitial case may liave hccn i q ~ o r t c d iii I95 I h y Catcl who descri1)ccI t w o sistcrs having muscle, horie, and joint tlis- ease Lei-met1 dysostosis enchoiitJralis rrietacpihy- saria. I'hese patients appear t o have demon- strated the typical features ol' SJS. Al)erfcld rc-re- ported Sc1iwar.t.z and Jampel's original patients i n lCKi.5 etnpliasi7ing tlic skeletalahnoi.in~ilities.' 'rhey also cnipliasizctl thc presence of m yotonia. Mereu descrit)ed two sililings with this disorder- in 196'3 and siiggcs red the naiiic Sell wart z -. J;im pt:l T h e inheritance pattern was pre- 7 . From the Departments of Neurology (Drs Pascuzzt, Gratianne. arid Kincaid) and Pathology (Dr. Azrarelli). Indiana University Medical Center, Indianapolis, Indiana Acknowledgment The authors thank Mrs Linda Hagan for assistance in preparation of the manuscript. Address reprint requests to Robert M. Pasci17c1, MD, Department of Neu- rology. 6th Floor Regenstriel Health Center, 1001 West 10th Street, lndt- anapolis, iN 46202. Accepted for publtcatiori Noverriber 24, 1989 CCC 0148-639X/90/01201152012 $04.00 G 1990 John Wiley & Sons, Inc sumctl t o he aittosonial recessive. FThose two sib- lings were Itt~ci- reviewed b y Aberf~cllcl ci al. aiitl la- t1cIecI as Ilii\rilig cIioritiro tlysiropIiic myotoni;r." Hutteiilocliei- et al. providetl tlic initial observa- lion of' c:ontiiiuous electrical activity in muscle at rest cIoc:iitneriteci tiy eIcc.troiriyogr-at)~iy. '' p icy z P la- heled the tlisortler as osteochondro clysti-ophy. Previous I-epoi-ts have emphasized the ailtosonla1 recessive iri1ierit;iiice patterti of SJS. We report the occiirrence of S j S in a f~ithei- ; i t i d son, suggest- ing the possililit y of cloniirmnt inheritancc. PATIENT #1 A 44 year-old man was referred IOr evaluation of ;I chronic iiciiroIiiiiscii1;ii~ disease in 1 !)80. His par- ents noted h i t ;it birth he had large, prominent iiiusclcs m t l tleveloped pi-ogressivc stiffiiess af- lecling tlic: 1iml)s early in childhootl. When he w;is a child, musc:le stiff'ncss affected his gait, a r i d he had difficulty attempting t o run. His stiffness was iitiafI'ecLet1 b y sustained exercise but aggravated by (.old exposure. Slowly progressive weakness of tlte limhs, par-ticularly the distal muscles gi-oups, was initially rioted diii.iiig adolescence along with early fiitigue during exercise. He sti.uggled in ris- ing fi-om ;i sitting position, in walking, aitcl with line, iq1etitivc use of' the ;ii-ins aiitl Iiaiicis, In his ~ O S , lie noted zyxw LKJI the tlevelopnicnt of' pei.sisterit low back ant1 proximal leg ac:hing paiii. fIis wilk oh- servccl that the distal extixxnitics, p;irticularly the fi ) reaim s ;in tl 11 ;ti i rls , s h o w ctl constant I i n e , (111 ive 1'- ing inoveiiieiits. 'l'hcse persisted during sleep. Heavy ingestion 01' swcet foods rc!sultcd in ;iii in- 1152 Schwartz-Jampel Syndrome MUSCLE & NERVE December 1990