E s te la M a ria N o v a k , C a rlo s A lb e rto L o n g u i, S e rg io P a u lo B y d lo w s k i
U n c o m m o n a lle le in A P O A I.C III.A IV
g e n e c lu ste r in a
fa m ily w ith c o n g e n ita l
g e n e ra liz e d Iip o d y stro p h y
R e s e a r c h a n d M o l e c u l a r B i o l o g y D i v i s i o n , P r ó - S a n g u e H e m o c e n t r o d e S ã o P a u l o F o u n d a t i o n , D e p a r t l 1 l e n t o f P e d i a t r i c s , F a c u l d a d e d e C i ê n c i a s M é d i c a s d a S a n t a C a s a d e S ã o P a u l o ,
D e p a r t m e n t o f H e m a t o l o g y , F a c u l d a d e d e M e d i c i n a - U S P - S ã o P a u l o , B r a z i l
C o n g e n ita l g e n e ra liz e d Iip o d y s tro p h y is a ra re in h e rite d d is e a s e . O n e o f its fe a tü re s is a d is tu rb a n c e in Iip id m e ta b o lis m c h a ra c te riz e d b y h y p e rc h o le s te ro le m ia a n d h y p e rtrig ly c e rid e m ia . A b ro th e r a n d a s is te r w ith c o n g e n ita l g e n e ra liz e d lip o d y s tro p h y , a n 8 -y e a r o ld m a l e a n d a 1 2 -y e a r o ld fe m a le w e re s tu d ie d . lh e m o th e r a n d a 6 -y e a r o ld b ro th e r w e re h e a lth y . lh e g e n e tic a n a ly s is o f 8 s tl R F L P o f th e a p o A I-C III-A IV g e n e c 1 u s te r s h o w e d th e p re s e n c e o f th e ra re 8 s tl a lle le (82) in th e p a tie n ts b u t n o t in th e h e a lth y m o th e r a n d b ro th e r. A s th is u n c o m m o n a lle le h a s b e e n re p o rte d to b e re la te d to h ig h p la s m a trig ly c e rid e le v e is , th is a s s o c ia tio n c o u ld b e re le v a n t in e x p la in in g in p a rt th e h y p e rtrig ly c e rid e m ia o b s e rv e d in th e s e p a tie n ts .
U N IT E R M S : A p o lip o p ro te in s . C o n g e n ita l g e n e ra liz e d Iip o d y s tro p h y . A p o A I-C III-A IV g e n e .
C
o n g e n ita lB e r a r d in e lli g e n e r a liz e ds y n d r o m e ) is a r a r elip o d y s tr o p h yh e r e d ita r y ( S e ipd is e a s e -in h e r ite d a s a n a u to s o m ic r e c e s s iv e tr a it. I ts m o s ts tr ik in g f e a tu r e s a r e e x tr e m e p a u c ity o f f a t in a d ip o s e tis s u e ,
in c r e a s e d g r o w th r a te , m u s c u la r /p s e u d o h y p e r tr o p h y , a r id
d is tu r b a n c e s o f c a r b o h y d r a te a n d lip id m e ta b o lis m
c h a r a c te r iz e d b y in s u lin r e s is ta n c e a n d h y p e r lip id e m ia . T h e
m e c h a n is m b e h in d th e s e a lte r a tio n s is u n c le a r .
T h e g e n e s c o d in g f o r a p o lip o p r o te in s ( a p o ) A - I , C - I I I ,
a n d A - I V a r e c lu s te r e d w ith in a 1 5 ~ K b D N A s e g m e n t o n th e
lo n g a r m o f h u m a n c h r o m o s s o m e 1 1 . S e v e r a l D N A
p o ly m o r p h is m s h a v e .b e e n id e n tif ie d in th is g e n e c lu s te r .
D ig e s tin g g e n o m ic D N A w ith r e s tr ic tio n e n d o n u c le a s e S s tl
y ie ld s tw o f r a g m e n ts a f te r h y b r id iz a tio n w ith a p o A I p r o b e :
5 .7 - K b a n d 4 .2 - K b in le n g th ( S I a lle le ) . I n m u ta te d a lle le s , a
3 .2 - K b f r a g m e n t ( S 2 ' r a r e a lle le ) is o b s e r v e d in s te a d o f th e
4 .2 - K b f r a g m e n te I t h a s p r e v io u s ly b e e n d e m o n s tr a te d th a t
A d d re s s fo r c o rre s p o n d e n c e : S e rg io P a u lo B y d lo w s k i,
A v . D r. E n é ia s d e C a rv a lh o A g u ia r, 1 5 5 - 1s t
flo o r S ã o P a u lo /S P - B ra s il - C E P 0 5 4 0 3 -0 0 0
th e r a r e a lle le ( S 2 ) c o u ld b e a s s o c ia te d w ith c e r ta in ty p e s o f
h y p e r lip o p r o te in e m ia in w h ic h h y p e r tr ig ly c e r id e m ia is a
f e a tu r el
. W e d e s c r ib e h e r e th e S s tl p o ly m o r p h is m o f th e
a p o A I - C I I I - A I V g e n e c lu s te r in a f a m ily w ith c o n g e n ita l
g e n e r a liz e d lip o d y s tr o p h y .
A b r o th e r a n d a s is te r w ith c o n g e n ita l g e n e r a liz e d
lip o d y s tr o p h y , a n 8 - y e a r o ld m a l e ( F .F .) a n d a 1 2 - y e a r o ld
f é m a le ( A .F .) , w e r e s tu d ie d . T h e m o th e r a n d a n o th e r b r o th e r
( 6 - y e a r o ld , R .F .) w e r e h e a lth y , a s s h o w n b y c lin ic a I a n d
la b o r a to r y e v a lu a tio n . T h e f a th e r h a d d ie d o f u n k n o w n c a u s e s
a n d it w a s n o t p o s s ib le to k n o w w h e th e r h e h a d s u f f e r e d
f r o m a n y d is e a s e . T h e c lin ic a I d ia g n o s is o f c o n g e n ita l
g e n e r a liz e d lip o d y s tr o p h y w a s m a d e w h e n th e c h ild r e n w e r e
b a b ie s . T h e - p a tie n ts ( F .F .a n d A .F .) h a d a c o m p le te a b s e n c e
o f a d ip o s e tis s u e . T h e y s h o w e d a c r o m e g a lo id a s p e c t w ith
m u s c u la r h y p e r tr o p h y a n d p h le b o m e g a ly , a b d o m in a l
p r o tr u s io n w ith h e p a to m e g a ly , a n d a c a n th o s is n ig r ic a n s .
A m o n g th e la b o r a to r y f in d in g s , th e p a tie n ts s h o w e d n o r m a l
f a s tin g b lo o d g lu c o s e , im p a ir e d g lu c o s e to le r a n c e a n d in s u lin
r e s is ta n c e . O th e r s tr ik in g f e a tu r e s w e r e h y p e r tr ig ly c e r id e m ia
a n d h y p e r c h o le s te r o le m ia w ith in c r e a s e d L D L - c h o le s te r o l
le v e I s .
N O V A K , E .M .; L O N G U I, C .A .; B Y D L O W S K I, S .P . - U n c o m m o n a lle le in A P O A I-C III-A IV g e n e c lu s te r in a fa m ily w ith c o n g e n ita l g e n e ra liz e d lip o d y s tro p h y
1 5 9 4
Figure 1 - M olecular analysis of S stl R FLP of the apoA I-C III-A IV gene cluster. 1 : m other; 2 :patient (A .F:)
kb
h y p e rtrig ly c e rid e m ia , a lth o u g h th e m e c h a n ism o f th is a sso c ia tio n re m a in s a n e n ig m a . A a Ito -S e tiiU i e t a I3h a v e fo u n dth e S 2 a n e le in 1 6 % o f h e a lth y c o n tro ls, 2 3 % o f p a tie n ts
w ith C H D a n d 6 2 % o f u n re la te d su b je c ts w ith
h y p e rtrig ly c e rid e m ia . T h e se d a ta a re in a c c o rd w ith R e e s e t
a l4 w h o d id n o t fin d a n y n o rm o lip e m ic in d iv id u a l c a rry in g
th e S 2 a lle le , b u t re p o rte d th e p re se n c e o fth is a n e le in 2 6 o u t
o f 7 4 h y p e rtrig ly c e rid e m ic su b je c ts. W e h a v e fo u n d th e S 2
a lle le in o n ly 2 % o f a n o rm o lip e m ic B ra z ilia n p o p u la tio n 2 .
O th e r in v e stig a to rs h a v e a lso in d ic a te d th a t th e re c o u ld b e a
sig n ific a n t re la tio n sh ip b e tw e e n lip id m e ta b o lism d iso rd e rs
a n d th e S stl p o ly m o rp h ism o f th e a p o A I-C III-A IV g e n e
c o m p le x in p a tie n ts w ith h y p e rtrig ly c e rid e m ia o r e v e n
h y p e rc h o le ste ro le m ia .
In th e p re se n t stu d y th e S 2 a lle le w a s p re se n t in th e
p a tie n ts w ith c o n g e n ita l g e n e ra liz e d lip o d y stro p h y a n d
a b se n t in th e h e a lth y m o th e r a n d b ro th e r.
In c o n c lu sio n , w e h a v e d e sc rib e d th e p re se n c e o f th e
u n c o m m o n a lle le S 2 in th e a p o A I-C III-A IV g e n e c lu ste r in
a fa m ily w ith c o n g e n ita l g e n e ra liz e d lip o d y stro p h y , w h ic h
c o u ld c o n trib u te to th e h ig h le v e Is o f p la sm a trig ly c e rid e s
o b se rv e d in th e p a tie n ts. M o re o v e r, a lth o u g h o n e c a n n o t
m a k e a n y in fe re n c e s a b o u t a lle lic a sso c ia tio n fro m o n ly
tw o c a se s in o n e fa m ily , th e p re se n t stu d y h a s p ro v id e d
a d d itio n a l e v id e n c e th a t g e n e tic v a ria tio n a t th is site c o u ld
b e in v o lv e d in h y p e rtrig ly c e rid e m ia .
A C K N O W LE D G M E N TS
T h is w o rk w a s su p p o rte d b y a g ra n t (1 0 /6 1 8 6 -7 ) fro m
F u n d a ç ã o B a n c o d o B .ra sil (S P B ).
T h e a u th o rs w ish to th a n k to D r. J.O rd o v a s (H u m a n N u tritio n R e se a rc h C e n te r, T u fts U n iv e rsity , B o sto n , M A )
h is h e lp in p ro v id in g th e p ro b e s u se d in th is stu d y . W e th a n k
M rs. A . N a k a y a m a fo r h e r a ssista n c e in p re p a rin g th e
m a n u sc rip t.
.7
3.2
4.2
D N A w a s iso la te d fro m th e n u c le a r fra c tio n o f 5 m l
o f v e n o u s b lo o d , a n d u se d fo r g e n o m ic b lo ttin g a n a ly sis.
R e stric tio n fra g m e n t le n g th p o ly m o rp h ism (R F L P ) stu d ie s
w ith re stric tio n e n d o n u c le a se S stl w e re p e rfo rm e d a s
d e sc rib e d 2 .
M o le c u la r a n a ly sis o f S stl R F L P o f th e a p o A I-C
III-A IV g e n e c o m p le x sh o w e d in th e m o th e r a n d y o u n g b ro th e r
th e 5 .7 - a n d 4 .2 -K b lo n g fra g m e n ts (g e n o ty p e S tS t)' w h ile
in th e p a tie n ts, 5 .7 ,4 .2 a n d 3 .2 - K b lo n g fra g m e n ts w e re
y ie ld e d (g e n o ty p e S IS 2 ) (F ig u re 1 ).
S e v e ra l g e n e tic m u ta tio n s h a v e b e e n lin k e d to
a lte ra tio n s in p la sm a lip o p ro te in s. It h a s b e e n su g g e ste d th a t
v a ria n t a n e le s o f th e n o n -c o d in g re g io n o f th e a p o A I~ C
III-A IV g e n e c lu ste r c o n stitu te a g e n e tic m a rk e r fo r
N O V A K , E .M .; LO N G U I, C .A .; B Y D LO W S K I, S .P . - U ncom m on allele in A P O A I-C III-A IV gene cluster in a fam ily w ith congenital generalized lipodystrophy
1595
REFERENCES
1 . T i b j a e r g - H a n s e n A , N o r d e s t g a a r d B G , G e r d e s L U ,
F a e r g e m a n O , H u m p h r i e s S E . G e n e t i c m a r k e r s i n t h e a p o
A I - C I I I - A I V g e n e c l u s t e r f o r c o m b i n e d h y p e r l i p i d e m i a ,
h y p e r t r i g l y c e r i d e m i a , a n d p r e d i s p o s i t i o n t o a t h e r o s c l e r o s i s .
A t h e r o s c l e r o s i s 1 9 9 3 ; 1 0 0 : 1 5 7 - 6 9 .
2 . B y d l o w s k i S P , N o v a k E M , I s s a J S , F o r t i N , G i a n n i n i S D ,
D i a m e n t 1 . D N A p o l y m o r p h i s n : t s o f a p o l i p o p r o t e i n s B a n d
A I - C I I I - A I V g e n e s i n a B r a z i l i a n p o p u l a t i o n : a p r e l i m i n a r y
r e p o r t e B r a z J M e d B i o l R e s 1 9 9 6 ; 2 9 : ' 1 2 6 9 - 7 4 .
3 . A a l t o - S e t a H i , K o n t u l a K , S a n e T , N i e m i n e n M , N i k k i l H i E .
D N A p o l y m o r p h i s m s o f a p o l i p o p r o t e i n A - I 1 C - I I I a n d i n s u l i n
g e n e s i n f a m i l i a l h y p e r t r i g l y c e r i d e m i a a n d c o r o n a r y h e a r t
d i s e a s e . A t h e r o s c l e r o s i s 1 9 8 7 ; 6 6 : 1 4 5 - 5 2 .
4 . R e e s A , S t o c k s , J , S h a r p e C R , e t a I . D e o x y r i b o n u c l e i c a c i d
p o l y m o r p h i s m i n t h e a p o l i p o p r o t e i n A I - C I I I g e n e c l u s t e r .
A s s o c i a t i o n w i t h h y p e r t r i g l y c e r i d e m i a . J C l i n I n v e s t 1 9 8 5 ;
7 6 : 1 0 9 0 - 5 .
N O V A K , E . M . ; L O N G U I , C . A . ; B Y D L O W S K I , S . P . - U n c o m m o n a lle le in A P O A I - C I I I - A I V g e n e c 1 u s t e r in a f a m ily w it h c o n g e n it a l g e n e r a liz e d lip o d y s t r o p h y
