ارتباط بين شاخص هاي خوني ناقلان آلفا تالاسمي با نوع جهش هاي ژني

مجله دانشكده بهداشت و انستيتو تحقيقات بهداشتي

دوره 7 - شماره 2

نوع مقاله: ---- Unspecified ----
چكيده:

زمينه و هدف : تالاسمي به عنوان يكي شايعترين بيماري تك ژني در ايران و جهان به حساب مي آيد. اين بيماري در سطح مولكولي هتروژن بوده و تا كنون علاوه بر حذف‌هاي بزرگ ، بيش از پنجاه جهش نقطه‌اي مختلف براي اين بيماري در سراسر دنيا شناخته شده است. در اين تحقيق ارتباط بين شاخص‌هاي خوني ناقلان آلفا تالاسمي ونوع جهش انان مورد بررسي قرار گرفت .
روش كار: با توجه به اينكه شاخص اصلي خوني ناقلان آلفا تالاسمي نسبت به افراد سالم ، كاهش ميزان MCV وMCH مي‌باشد اين تحقيق و برروي 208 كروموزم ( به ترتيب 33 ناقل آلفا تالاسمي استان خوزستان و71 ناقل آلفا تالاسمي استان خراسان) انجام گرفت. ناقلان بين 20 تا 40 سال سن داشته‌اند و با هم وابستگي فاميلي نداشتند.
نتايج: تنها يك نوع جهش °a بدست آمد (MED). اين جهش در 9/2% جمعيت مورد مطالعه ديده شد. ناقلان اين جهش از متوسط MCV معادلfL 63/90 برخورداربودند. اين در حالي بود كه ناقلان آلفا تالاسمي با ساير هشت جهش يافت شده + a (درمجموع ده ژنوتيپ)، داراي MCV بالاتري نسبت به گروه قبلي بودند (2/77>MCV>68/4).
نتيجه‌گيري : نتايج تعيين كننده ارتباط مستقيم بينMCV و MCH با شدت جهش ( +aو °a) ميباشد علاوه برآن ميزان MCV و MCH در ناقلان آلفا تالاسمي مي‌تواند بعنوان يك الگوي با ارزش، جهت تشخيص سريع نوع جهش در جمعيت ايران به كار برده شود.

Assocaition between hematological indices and types of gene mutations in alpha thalassemia carriers
Article Type: ---- Unspecified ----
Abstract:

Background and Aim: Thalassemia is one of the most common worldwide single-gene diseases. On the molecular level, it is a heterogeneous disease. So far, beside large deletions, more than fifty point mutations have been identified for this disease around the world. Four to ten percent of Iranians are carriers of thalassemia-affected genes. In this study we determined the relationship between the value of MCV/MCH and the type and severity of mutations in alpha thalassemia carriers.
Methods and Materials: The major abnormality in alpha thalassemia carriers is decreased values of MCV and MCH. A total of 104 adult alpha thalassemia heterozygotes, 20-40 years old, including 33 persons from Khoozestan Province and 71 from Khorasan Province, were included in the study. Two hundred and eight chromosomes were isolated from peripheral blood leukocytes using standard procedures. DNA samples were amplified by Gap-PCR.
Results: Only one α° mutation (MED) was found in 2.9% of the population. The carriers of this mutation had virtually identical ranges of MCV and MCH. In contrast, α+ mutations were associated with significant differences in mean MCV and MCH values. The various mean MCV/MCH ratios of α° carriers were statistically significantly lower than those of α+ heterozygote. The results indicated that the degree of reduction in MCV and MCH is directly related to the severity of the mutations. Deviations, in cases, were associated with lower numbers of the carriers.
Conclusion: Only one α° mutation (MED) was found in 2.9% of the population. The carriers of this mutation had virtually identical ranges of MCV and MCH. In contrast, α+ mutations were associated with significant differences in mean MCV and MCH values. The various mean MCV/MCH ratios of α° carriers were statistically significantly lower than those of α+ heterozygote. The results indicated that the degree of reduction in MCV and MCH is directly related to the severity of the mutations. Deviations, in cases, were associated with lower numbers of the carriers.

قیمت : 20,000 ريال