【佳學(xué)基因檢測】羅馬諾-沃德綜合征綜合征基因解碼、基因檢測

來源：基因解碼基因檢測是解決
作者：佳學(xué)基因檢測
時(shí)間：2018-06-23 05:32
閱讀數(shù)：次

羅馬諾-沃德綜合征是英文Romano-Ward syndrome的中文翻譯，它又叫羅馬-沃德綜合征，RWS綜合征。是一種常染色體顯形遺傳的長QT綜合征(LQTS)，臨床表現(xiàn)為反反復(fù)作的暈厥、抽搐、致命性心律失常(特別是由于心臟復(fù)極延長所致先進(jìn)扭轉(zhuǎn)型室速)和猝死。佳學(xué)基因通過基因解碼技術(shù)在發(fā)病前、婚前、孕前分析發(fā)病原因，避免胎兒的再次出生，并為患者提供針病因的治療依據(jù)。

【佳學(xué)基因檢測】羅馬諾-沃德綜合征 綜合征基因解碼、基因檢測

基因解碼導(dǎo)讀：

什么樣的人應(yīng)當(dāng)做羅馬諾-沃德綜合征基因解碼、基因檢測？

患者心臟節(jié)律紊亂，心律失常。這種病癥是一種長QT綜合癥，心臟（心臟）肌肉比正常人花費(fèi)更長的時(shí)間在心跳間重新充電。術(shù)語“長QT”是指用心電圖（ECG或EKG）檢測心臟活動(dòng)時(shí)出現(xiàn)的一種心電圖模式。在長QT綜合征的患者中，稱為QT間期的部分心跳異常長。心臟充電所需時(shí)間異常導(dǎo)致心律異常。與羅馬 - 沃德綜合征相關(guān)的心律失常可導(dǎo)致昏厥（暈厥）或心臟驟停和猝死。但是，一些患有羅馬 - 沃德綜合征的人從未遇到任何與該病有關(guān)的健康問題。基因解碼根據(jù)基因序列明確了15種長QT綜合征。某些類型的長QT綜合征有心臟異常或其他系統(tǒng)問題。羅馬 - 沃德綜合征是指那些只有長QT間期而沒有其他異常的類型。

羅馬諾-沃德綜合征常規(guī)臨床檢查

臨床表現(xiàn)

根據(jù)ECG特征譜、臨床表征和家族史，得出羅馬諾-沃德綜全征的初步診斷.

ECG檢查

Corrected QT (QTc) values on resting ECG. The QTc on resting ECG is neither completely sensitive nor specific for the diagnosis of LQTS. Approximately 25% of individuals with LQTS confirmed by the identification of a pathogenic variant in a LQTS-associated gene may have a normal range QTc (concealed LQTS) [Goldenberg et al 2011]. Also, several other factors can lengthen the QTc interval:

QT-prolonging drugs
Hypokalemia
Certain neurologic conditions including subarachnoid bleed
Structural heart disease

The following tests are helpful for further evaluation of individuals with "uncertain" QTc values on resting ECG:

Exercise ECG, which commonly shows failure of the QTc to shorten normally and even prolongation of the QTc interval [Jervell & Lange-Nielsen 1957, Vincent et al 1991, Swan et al 1998, Horner et al 2011, Sy et al 2011]. Many individuals develop characteristic T-wave abnormalities [Zhang et al 2000].
QTc interval measurement during change from supine to standing position [Viskin et al 2010]
Intravenous pharmacologic provocation testing (e.g., with epinephrine), which may be helpful by demonstrating inappropriate prolongation of the QTc interval [Ackerman et al 2002]. With the small risk of induction of arrhythmia, such provocative testing is best performed in laboratories experienced in arrhythmia induction and control [Shimizu et al 2004, Vyas et al 2006].

Clinical History

A personal history of syncope, aborted cardiac arrest, or sudden death in a child or young adult may lead to suspicion of LQTS. The syncope is typically precipitous and without warning, thus differing from the common vasovagal and orthostatic forms of syncope in which presyncope and other warning symptoms occur. Absence of aura, incontinence, and postictal findings help differentiate LQTS-associated syncope from seizures.

Family History

A family history of syncope, aborted cardiac arrest, or sudden death in a child or young adult and consistent with autosomal dominant inheritance or autosomal recessive inheritance supports the diagnosis of LQTS.

Establishing the Diagnosis

Schwartz et al [1993] proposed a scoring system to diagnose LQTS on a clinical basis; it was updated by Schwartz & Crotti [2011]. Points are assigned to various criteria (see Table 1).

Table 1.

Scoring System for Clinical Diagnosis of Long QT Syndrome

Findings			Points
ECG 1	QTc 2	≥480 ms	3
		=460-479 ms	2
		=450-459 ms (in males)	1
		≥480 ms during 4th minute of recovery from exercise stress test	1
	Torsade de pointes 3		2
	T wave alternans		1
	Notched T wave in 3 leads		1
	Low heart rate for age 4		0.5
Clinical history	Syncope 3	With stress	2
Clinical history	Syncope 3	Without stress	1
Family history	Family member(s) with definite LQTS 5		1
Family history	Unexplained sudden cardiac death at age <30 years in immediate family 5		0.5
Total score

: Adapted from Schwartz & Crotti [2011]
: Scoring:
: ≤1.0 point = low probability of LQTS
: 1.5-3.0 points = intermediate probability of LQTS
: ≥3.5 points = high probability of LQTS
: Footnotes:
1.: In the absence of medications or disorders known to affect these electrocardiographic features
2.: QTc (corrected QT) calculated by Bazett's formula where QTc = QT/√RR
3.: Mutually exclusive
4.: Resting heart rate <2nd %ile for age
5.: The same family member cannot be counted for both criteria.

The diagnosis of LQTS is established in a proband with one or more of the following [Priori et al 2013]:

A risk score of ≥3.5 (see Table 1) in the absence of a secondary cause for QT prolongation
The presence of a corrected QT interval ≥500 ms in repeated ECGs in the absence of a secondary cause for QT prolongation
The identification of a pathogenic variant in one of the known to be associated with LQTS (see Tables 2a and 2b)

羅馬諾-沃德綜合征基因解碼

致病基因：

根據(jù)《人的基因序列變化與人體疾病表征》數(shù)據(jù)庫，佳學(xué)基因發(fā)現(xiàn)和明確了可以引起羅馬諾-沃德綜合征的基因。導(dǎo)致這一疾病發(fā)生的基因有多個(gè)，K***1，K***2和S****A基因突變是羅馬 - 沃德綜合征最常見的致病基因。這些基因編碼、控制合成人體細(xì)胞膜通道。這些通道蛋白將帶正電荷的離子（如鉀和鈉）輸運(yùn)進(jìn)、運(yùn)出細(xì)胞。在心肌細(xì)胞中，這些離子通道蛋白在維持心臟正常節(jié)律方面起著關(guān)鍵作用。基因解碼揭示任何這些基因的突變改變了通道蛋白的結(jié)構(gòu)或功能，影響了離子進(jìn)入細(xì)胞的活動(dòng)。從而改變心臟的跳動(dòng)方式，導(dǎo)致羅馬諾 - 沃德綜合征的心律異常。佳學(xué)基因解碼提請(qǐng)注意，其他參與離子轉(zhuǎn)運(yùn)的基因突變也可以導(dǎo)致羅馬 - 沃德綜合征，基因檢測如果沒能覆蓋這些基因?qū)е轮虏』蜩b定失敗?；虻膹?fù)合作用也是疾病發(fā)生的原因。。

遺傳方式：

根據(jù)佳學(xué)基因《人的基因序列變化與人體疾病表征》數(shù)據(jù)庫，羅馬諾-沃德綜合征主要按常染色體顯性模式遺傳，但是個(gè)性化的發(fā)病原因，會(huì)使得不同患者的遺傳模式表現(xiàn)不同。在顯性遺傳中，兩個(gè)等位基因中的任何一個(gè)發(fā)生突變都會(huì)導(dǎo)致患者生病?；颊吒改竿鶗?huì)有一個(gè)患者。但是，子女也可能因?yàn)樾掳l(fā)突變而致病，這時(shí)發(fā)病原因不是來自父母。使這種情況變得復(fù)雜的是，佳學(xué)基因發(fā)現(xiàn)這一疾病的外顯率在部分患者會(huì)降低。這意味著父母不患病時(shí)，子女有可能患病。同樣，父母不患病，在子女中有可能發(fā)生外顯而患病。通過基因解碼明確這些有助于防范。這主要是因?yàn)檫@一疾病的突然來臨，會(huì)奪取人的生命。。

羅馬諾-沃德綜合征基因解碼可以區(qū)分：

心臟病
心肌梗死
不同類型的長QT綜合生

突變基因	不同類型的LQTS	人群占比
A*9	LQTS type 11	Limited
A2	LQTS type 4	<1%
C**C	LQTS type 8	<1%
C1	LQTS type 14	<1%
C*2	LQTS type 15	<1%
C3	LQTS type 9	<1%
K*1	LQTS type 5	<1%
K*2	LQTS type 6	<1%
K*2	LQTS type 7	<1%
K*5	LQTS type 13	<1%
S*B	LQTS type 10	Limited
S*1	LQTS type 12	<1%