Genetic Disorders: Experience in Saudi Arabia …kau.edu.sa/Files/287/Files/67545_Genetic Disorders...
-
Upload
truongtram -
Category
Documents
-
view
212 -
download
0
Transcript of Genetic Disorders: Experience in Saudi Arabia …kau.edu.sa/Files/287/Files/67545_Genetic Disorders...
InThe Medical Genetic Unit of King Abdulaziz University in Jeddah was established by the author in February 2005. It contains the first genetic clinics in the Western region of the Kingdom of Saudi Arabia. Jeddah, the commercial capital and the second largest city of Saudi Arabia, has a population of over 3.5 million people with a 2.06% growth rate and the median age of 21.4 years. Referrals are received from Jeddah and surrounding cities and towns in the Western Region including among others Makkah, Taif, and Al-Baha. The objectives of this prospective study were to study the pattern of genetic disorders over a 4 year period, elucidate their inheritance patterns, set up a platform for a genetic database in the region and identify the relevant risk factors for genetic conditions in our population, especially those which are potentially preventable. Nine hundred and four patients with genetic disease have been assessed. Each patient received a full genetic assessment including s dysmorphological examination. Imaging and laboratory testing (including genetic testing) were done as appropriate. The most likely inheritance pattern was based on the diagnosis and analysis of family pedigree. The most common form of genetic disease was autosomal recessive followed by chromosomal disorders and then autosomal dominant disorders. Unlike some other reports from Saudi Arabia, consanguinity was more likely to be present in individuals with autosomal recessive disorders than with any other form of genetic disease including isolated congenital malformations. Recommendations to decrease the burden of genetic disease in this region including our experience with the current Premarital Screening in our student population are discussed.
Population of Saudi Arabia is a mixture of ethnic groupsSpecific genetics and cultural factors Consanguinity rates: 2560%-Diminished awareness of the importance of genetic counseling in preventing malformations
Study the pattern of genetic disorders at the western region of KSA over a 24 month periodElucidate the inheritance patterns for these genetic disordersDetermine the relevant risk factors for genetic conditions in this population- especially those that are potentially preventableProvide recommendations for reduction of genetic disorders- role of genetic counseling and feasibility of antenatal diagnosis
Cosmopolitan cityPopulation >3 millionCommercial capital of Saudi ArabiaWestern coast of the Red SeaMulticultural societyHeterogeneous population
Comparison of advanced maternal age between individuals with trisomies vs. all other groups :Trisomies: 60% of mothers were of AMA.Others: 27.6% of mothers were of AMA.
Unlike some other reports from Saudi Arabia, consanguinity was more likely to be present in individuals with autosomal recessive disorders (56.25% ) than with any other form of genetic disease ( 22.9%)including isolated congenital malformationsIn 38.8% of infants with congenital malformations the parents were consanguineous.
Estimated recurrence risk of genetic disorders is > 1% in almost all cases and more than half RR ≥ 25%.Overall 32.61% of all cases had a RR >1% AND Antenatal diagnosis was possible and feasibleThe need for genetic counseling is underscored by the fact that 55.4% of mothers were <36 years and likely to have further children.Factors amenable to premarital and preconception counseling and more common in the region are consanguinity and advanced maternal age.A condensed public education program in addition to education of all health care providers who can play an essential role will be highly cost effective in reducing the burden in genetic disorders in the KSA.
BACKGROUND
JEDDAH
ABSTRACT
Distribution of Underlying Etiology
OBJECTIVES
QuickTime™ and aGraphics decompressor
are needed to see this picture.
0
10
20
30
40
50
60
70
80Types of Chromosomal Disorders
DS (N
D)
DS (t
ranslo
catio
n)Tri
somy 1
8Tri
somy 1
3De
letion
Microd
eletio
n
other
05
101520253035
Most common Autosomal Dominant Disorders
Noon
an sy
ndrom
e
Achon
dropla
siaEh
ler-da
nlos
Marfan
Synd
rome
CDL
Coste
llo Sy
ndrom
e
Rubin
stein-
taybi.
..O.l t
ype 1
other
233329
141111
DMD Fragile X
X-linked hydrocephalusAicardi syndrome
Simpsom-Golabi-Behmel syndromeLesch Nyhan syndrome
Retinitis pigmentosa (x-linked type)orotic aciduria
X-linked Thalassemia with mental retardationRett syndrome
Oro-facial digital syndrome (OFD) type II
Diagnosis No.
X-linkd Disorders
Cerebellar Dygenesis
CDP
Cockayne syndrome
Collodion baby
Congenital Adrenal hyperplasia
Congenital myopathy
Congenital nephrotic syndrome
Sonada-Kaouna
Dubowitz syndrome
JEB
Ehlers-Danlos syndrome,
type VI
Familial hypermagnesemia
GSD type III
Hurler syndrome
Jarcho-levin syndrome
Joubert syndrome
Neimann-Pick Disease
Neurodegenerative disease
O. I. type 3
O. I.
PKU
Retinitis pigmentosa
RCDP type 1
Russel Silver syndrome
Sanjad-Sakati syndrome
SCA
Seckel syndrome
SMA
Spinocerebellar Ataxia
Tay-Sach Disease
Walker-Warburg syndrome
Wolcott-Rallison syndrome
Xeroderma pigmentosa
The Most Common Autosomal Recessive Disorders
CONSANGUINITY
CONCLUSIONS:
Genetic Disorders: Experience in Saudi Arabia Jumana Y. Al-Aama, Alaa Y.Edrees
Princess Al Jawhara Center of Excellence in the Research of Hereditary Disorders,King Abdul-Aziz University, Jeddah, Saudi Arabia